2004.11c
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Cleft lip is one of the most common congenital deformities in craniofacial region. Despite the many reports on the outcome of various surgical techniques from individual medical centers, the evaluation of the outcome is based on the subjective observation because of lack of the objective evaluation system. Therefore, a new technique of objective and scientific evaluation for the nasal deformity of secondary cleft lip and nose deformity is critical to improve the management of the cleft patients including the decision of optimal age of operation and surgical technique as veil as evaluation of the outcome. In this study, a new method was proposed to evaluate the nasal deformity using nostril angle, distance, and area of patient images. The images were also evaluated by three expert plastic surgeons, and put into scale of 5 percentile. Measurement results were compared between the each category and the surgeon's evaluation, and coefficients of each category were statistically tested. As a result, The normalized overlap area of right and left nostrils and distance ratio between two centers of nostrils showed high coefficient with evaluations of plastic surgeons.
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The objective of this paper is to develop a powered wheelchair controller based on EMG for users with high-level spinal cord injury using a proportional control scheme. An advantage of EMG is relative convenience of acquisition by a surface electrode to users. Direction information can be easily extracted from two EMG channels and force information can be acquired by proportional relationship between the amplitude of EMG and user's power, respectively. Pattern classification algorithm is a threshold method with a supervised learning process. Furthermore, the emergency situation can be avoided using an interrupt function. We evaluated the performance of powered wheelchair controller by navigating a pre-defined path with three non-handicapped people. The results show the feasibility of EMG as an input interface for powered wheelchair and other devices for the seriously disabled.
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The vocal folds play an important role to produce glottal pulse which is an essential factor of phonation. There have been some models which implement the vocal folds' dynamics, such as one-mass model, two-mass model, multi-mass model and ribbon model. Among them, this paper uses nonlinear two-mass model, which is simple structure and produces similarly real glottal pulses and vocal folds' vibration, to realize vocal folds digital model. The pattern of movements in vocal folds will be shown in this paper by using vocal folds digital model. It will be verified how initial position of vocal folds. variation of tension and change of lung pressure influences vibration and glottal pulses.
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In this paper, it is implemented the monitoring system for TV advertisement using video watermark. The functions of an advertisement monitoring system are automatically monitoring for the time, length, and index of the on-air advertisement, saving the log data, and reporting the monitoring result. The performance of the video watermark used in this paper is tested for TV advertisement monitoring. This test includes LAB test and field test. LAB test is done in laboratory environment and field test in actually broadcasting environment. LAB test includes PSNR, distortion measure in image, and the watermark detection rate in the various attack environment such as AD/DA(analog to digital and digital to analog) conversion, noise addition, and MPEG compression The result of LAB test is good for the TV advertisement monitoring. KOBACO and SBS are participated in the field test. The watermark detection rate is 100% in both the real-time processing and the saved file processing. The average deviation of the watermark detection time is 0.2 second, which is good because the permissible average error is 0.5 second.
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In many cases, human's visual recognition depends on contextual information. We need to use effective feature information for performing vigorous place recognition to illumination, noise, etc. In the existing cases that use edge and color, etc., visual recognition doesn't cope effectively with real environment. To solve this problem, using natural marker, we improve the efficiency of place recognition.
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This paper proposes a printing quality inspection system of film-type envelopment. Since the printing system is running at very high-speed (140m/min.) and the line error has very narrow width, we have to choose one-dimensional high-speed and high-resolution line scan camera. The vibration of the printing machine and the illumination environment make the inspection problem more harder. To obtain reliable inspection results, many software image processing techniques are applied and many parameters are tuned. The performance of the proposed system is proved by many simulations and long time real-plant experiments.
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Sensor Model Design of Range Sensor Based Probabilistic Localization for the Autonomous Mobile RobotThis paper presents a sensor model design based on Monte Carlo Localization method. First, we define the measurement error of each sample using a map matching method by 2-D laser scanners and a pre-constructed grid-map of the environment. Second, samples are assigned probabilities due to matching errors from the gaussian probability density function considered of the sample's convergence. Simulation using real environment data shows good localization results by the designed sensor model.
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With 3-D vision measuring, camera calibration is necessary to calculate parameters accurately. Camera calibration was developed widely in two categories. The first establishes reference points in space, and the second uses a grid type frame and statistical method. But, the former has difficulty to setup reference points and the latter has low accuracy. In this paper we present an algorithm for camera calibration using perspective ratio of the grid type frame with different line widths. It can easily estimate camera calibration parameters such as lens distortion, focal length, scale factor, pose, orientations, and distance. The advantage of this algorithm is that it can estimate the distance of the object. Also, the proposed camera calibration method is possible estimate distance in dynamic environment such as autonomous navigation. To validate proposed method, we set up the experiments with a frame on rotator at a distance of 1, 2, 3, 4[m] from camera and rotate the frame from -60 to 60 degrees. Both computer simulation and real data have been used to test the proposed method and very good results have been obtained. We have investigated the distance error affected by scale factor or different line widths and experimentally found an average scale factor that includes the least distance error with each image. The average scale factor tends to fluctuate with small variation and makes distance error decrease. Compared with classical methods that use stereo camera or two or three orthogonal planes, the proposed method is easy to use and flexible. It advances camera calibration one more step from static environments to real world such as autonomous land vehicle use.
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In this paper, web based monitoring systems are implemented for multi-axis force control systems of an intelligent robot. Linux operating systems are ported to an embedded system which Include a Xscale processor to implement a web based monitoring system. A device driver is developed to receive data from multi-axis force sensors of intelligent robots. To control this device driver, a socket program for Labview is also developed.
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We have designed a portable electronic nose(e-nose) system using an array of commercial gas sensors for recognition and analyzing the various odours. In this paper, we have implemented a portable e-nose system using an array gas sensors and personal digital assistants(PDA) for recognizing and analyzing volatile organic compounds(VOCs) in the field. Field screening for pollutants has been a target of instrumental development for number of year. A portable e-nose system can be substantial benefit to rapidly localize the spacial extent of a pollution or to find pollutants source. And, by using PDA, E-nose have a better function such as the easy user-interface and data transfer by internet from on- site to remote computer. We adapted the Levenberg-Marquardt algorithm based on the back-propagation and proposed the method that could be predicted concentration levels of VOCs gases after classification by separating neural network into two parts.
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A remote monitoring system was developed to improve inconveniences of manual work such as monitoring street lights by using current sensors, microprocessor and RF communication system. In order to control the street lights on the roads effectively and monitor them in real time, we can attach current sensor to the street lights which monitors Lamp, the broken part and state of the Balast, and the amount of an electric leak precisely we developed a system which makes it possible to transmit the data on monitoring results in breakdown of street lights and Balasts to the central monitoring computer without setting up extra data transmission line. The system we devised can transmit data through Power Line Modem and RF communication using relay method to the central controlling computer without any loss of data.
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This paper presents a simple method of rotational and translational motion estimation for digital image stabilization. The scheme first computes the rotation center by taking least squares of selected local velocity vectors, and the rotational angle is found from special subset of motion vectors. And then translational motion can be estimated by the relation among movement of rotation center, rotation angle and translation movement. To show the effectiveness of our approach, the synthetic images are evaluated, resulting in better performance.
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This paper presents a realization of fault detection algorithm and Fieldbus based communication for condition monitoring of check valve. We first acquired the AE(Acoustic Emission) sensor data at the KAERI check valve test loop, extract fault features through the learned Neural network, and send the processed data to a remote site. The overall system has been implemented and experimental results are given to show its effectiveness.
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Digital communication networks have become a core technology in advanced building automation systems. BACnet(
${\underline{B}}uilding$ ${\underline{A}}utomation$ and${\underline{C}}ontrol$ ${\underline{net}}works$ ) is a standard data communication protocol designed specifically for building automation and control systems. BACnet adopts Master-Slave/Token-Passing (MS/TP) protocol as one of its field level networks. In this study, we introduce a method of implementing bandwidth allocation scheme in the MS/TP protocol. The bandwidth allocation scheme improves the capability of real-time communication of the original MS/TP protocol. The bandwidth allocation scheme introduced in this paper can be easily implemented in the existing MS/TP protocol with a slight modification. In this study, we actually developed the hardware and firmware of MS/TP module in which bandwidth allocation scheme is implemented. -
For automatic landing of small VTOL UAV, it is necessary to calculate the distance from the UAV and the ground. The distance can be generally measured by a ultra-sonic sensor, but the ultra-sonic sensor has errors according to velocity of a sensor board. To compensate these errors, we proposed a sensor fusion method using a Kalman filter.
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An optimal robust controller design method for gun driving system is discussed in this paper. The parameters of the gun driving controller are tuned by using the LQR characteristics for the performance and robustness. Tuning method that optimize velocity error gives a significant improvement over the existing PID tuning methods. It is shown that the tuning result of real gun driving system which is regarded as rigidness model or stiffness model satisfy performance and robustness.
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PID제어기를 플랜트 파라미터를 이용하여 구성하는 IMC-PID제어에 대해 연구한다. 특히 변하는 플랜트에 대해서는 자기동조(ST, Self-Tuning)를 사용하여 시스템을 식별하여 활용한다. 특히 실시간으로 개루프의 위상여유 및 이득여유를 모니터링하여 정해진 구역을 벗어나게 되면 식별된 시스템파라미터를 이용하여 IMC-PID제어기를 구성한다. 또 시간영역 지표로 과도한 오차가 발생하는 경우에도 제어기를 갱신함으로서 전체적으로 보면 견실 PID제어기 형태를 갖게 한다.
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DC servo motors have a defect that they need a periodical maintenance because of a brush commutation and also they have a difficulty at high speed operation. In this reason, the use of AC Servo motors are increasing these days. In this paper, a proposed neuro observer is applied to speed control of AC servo motor. The proposed observer complement a problem that occur from increase of gain of High-gain observer in proportion to the square number of observable state variables. And also, the proposed observer can tune the gain obtained by differentiating observational error automatically by using the backpropagation training method to stabilize the observational speed. The excellence and feasibility of the proposed observer is proved by making a comparison test between the proposed observer and the others applied to the same AC servo motor.
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In this paper, the task assignment strategy considering communication delay and the priority of distributed tasks is proposed for the real-time network system in order to maximize the utilization of the system. For the task assignment strategy, the relationship among priority of tasks in network nodes, the calculation time of each task, and the end-to-end response time including the network delay is formulated firstly. Then, the task assignment strategy using the genetic algorithm is proposed to optimize the utilization of the system considering the LCM(Least Common Multiple) period. The effectiveness of proposed strategy is proven by the simulation for estimating the performance such as the utilization and the response time of the system in case of changing the number of tasks and the number of network nodes.
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LQ-Servo controller inherits the stability-robustness from rational LQR structure and also, satisfies performance-robustness that is lacking in LQR structure by importing partial output feedback. In this paper, LQ-Servo controller is suggested for strengthening the performance-robustness. For this, Several executings are effectively performed by implementing to the rotational inverted pendulum system.
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This paper proposes the development of delay compensator to minimize performance degradation caused by time delays in network-based real-time control systems. The delay compensator uses the time-stamp method as a direct delay measuring method to measure time delays generated between network nodes. The delay compensator predicts the network time delays of next period in the views point of time delays and minimizes performance degradation from network through considering predicted time delays. Control output considering network time delays is generated by the defuzzification of probable time delays of next period. The time delays considered in the delay compensator are modeled by using a timed Petri net model. The proposed delay prediction mechanism for the delay compensator is evaluated through some simulation tests by measuring deviation of the predicted delays from simulated delays.
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As the rapid incensement of the number of internet users has occurred recently, many multimedia application services have been emerging. To improve quality of service, traffic can be suggested to be classified with priority in EPON(Ethernet Passive Optical Network), which is supporting the multimedia application services. In this paper, multimedia application services treat bandwidth classifying device in serving both delay sensitive traffic for real-time audio, video and voice data such as VoIP(Voice over Internet Protocol), and nonreal-time traffic such as BE(Best Effort). With looking through existing mechanisms, new mechanism to improve the quality will be suggested. The delay performances and packet losses of traffic achieved by supporting bandwidth allocation of upstream traffic in suggested mechanism will be analyzed with simulation.
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In SCADA systems, an RTU is a device installed at a remote location that collects data, codes the data into a format that is transmittable and transmits the data back to a central station, or MTU. An RTU also collects information from the master device and implements processes that are directed by master device. RTUs are equipped with input channels for sensing or metering, output channels for control, indication or alarms and a communications port. In general, the data are transmitted via a wired communication infrastructure such as RS422 or RS485 between RTU and MTU. But, limited range of wired communication doesn't allow the system to cover remote areas over the limitation, and building a wired communication network is not easy in the circumstances. In this Paper, we design and implement a smart cost-effective Web-RTU that can communicate with MTU via Web. Web is of benefit to the Web-RTU, because it is not only free from the distance limitations, but also is built easily and cost-effectively wherever Internet resources are available. Additionally, Web can be easily applied to the SCADA system with the development of hardware and software for communications. The Web-RTU has a program memory, a data memory and a RAM inside, and uses Atmega128, low-cost 8 bit micro-processor with eight AI(Analog Input). It performs well enough to implement all existing roles of RTU.
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In the previous work, we proposed a new stability criterion for the stability of switched linear systems. By the proposed criterion, we could simply check the stability of switched linear systems because the criterion is applicable to each individual subsystem without need to consider the overall system. Using this criterion, we provided the methods that design a state feedback control when full states are available. In this paper, we apply the same criterion to the case when full states are not available. Unlike existing method such as dwelling time analysis, the proposed method is suitable to a fast switching process because there is no need to consider dwelling time. And we can easily achieve designing multi-controller, multi-estimator, and the supervisor by means of the proposed method.
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This paper proposed new IMC-PID controller design method that use loop shaping method. It could consider such design specifications as gain margin, phase margin, sensitivity function etc by appling the loop shaping method for tuning IMC-PID controller whose structure has only one design parameter and guarantees internal stability. To shape desirable loop gain, the relation between these design specification and parameter is derived by mathematical basis. And the availability of proposed in this paper tuning method that can regard design specifications is checked through example comparison and analysis.
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Expansible & Reconfigurable Neuro Informatics Engine(ERNIE) is effective in reconfigurability and extensibility. But ERNIE have the problem which have limited performance in initial network. To solve this problem, the constructive module using the reconfigurable ERNIE is implemented in simulation model. In this paper, simulation results on sonar data are showed that ERNIE using the constructive module obtains the better performance compared to ERNIE without it.
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There are many under grounds facilities like oil pipes, gas pipes, water pipes, oil tanks, etc. and severe corrosion of these facilities made big problems. Fire, wide area water and soil pollution, massive and hazardous explosion, etc. can make big problems and cause big economical loss. So, various technologies were developed to keep these undergrouns facilities safely, and cathodic protection is one of it. For cathodic protection, one must detect potential of pipes, and there are so many test box to check pipes potentials. In this thesis, we describe on the development of small size corrosion monitoring system that measure pipes potentials easily and economically.
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In this paper, authors propose the sensor fusion system that can recognize multiple 3D objects from 2D projection images and tactile information. The proposed system focuses on improving recognition performance of 3D object. Unlike the conventional object recognition system that uses image sensor alone, the proposed method uses tactual sensors in addition to visual sensor. Neural network is used to fuse these informations. Tactual signals are obtained from the reaction force by the pressure sensors at the fingertips when unknown objects are grasped by four-fingered robot hand. The experiment evaluates the recognition rate and the number of teaming iterations of various objects. The merits of the proposed systems are not only the high performance of the learning ability but also the reliability of the system with tactual information for recognizing various objects even though visual information has a defect. The experimental results show that the proposed system can improve recognition rate and reduce learning time. These results verify the effectiveness of the proposed sensor fusion system as recognition scheme of 3D object.
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A delay dependent fuzzy
$H_{\infty}$ controller design method for delayed nonlinear systems with parameter uncertainty is considered. Using delay-dependent Lyapunov function the asymptotical stability and$H_{\infty}$ n performance problem :are discussed. A sufficient condition for the existence of fuzzy controller is presented in terms of linear matrix inequalities(LMIs). A simulation example through radar gimbal system is given to illustrate the design procedures and performances of the prosed methods. -
The temperature profile control issue in the resistive welder for the electronic parts is discussed. The average current of the welder tip depends on the phase(on-time) of the AC power and the tip temperature maintains or increases/decreases depending on the integral of the current square and heat loss, The basic PID control algorithm with thermo-couple feedback is difficult to track the temperature profile for various parts and optimal gain changes much. So constant gain PID algorithm is not enough to cover various electronic parts welding and a Fuzzy-PID automatic gain tuning algorithm is devised and added to conventional PID algorithm and this hybrid control architecture is implemented and the experimental results are shown.
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In order to successfully exploit underwater resources, the first step would be a marine environmental research and exploration on the seafloor. Traditionally one sets up a long-term underwater experimental unit on the seafloor and retrieves the unit later after a certain period time. Essential to these applications is the reliable teleoperation and telemetering of the unit. This study presents ultrasonic-wave remote control system and an underwater sound recognition algorithm that can identify the sound signal without the influence of disturbances due to underwater environmental changes. The proposed method provides a means suitable for units which require low power dissipation and long-time underwater operation. We demonstrate its ability of securing stability and fast sound recognition through experimental methods.
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The importance for Internet security has being increased and the Internet Protocol Security (IPSec) standard, which incorporates cryptographic algorithms, has been developed as one solution to this problem. IPSec provides security services in IP-Layer using IP Authentication Header (AH) and IP Encapsulation Security Payload (ESP). In this paper, we propose IPSec cryptographic processor design based AMBA architecture. Our design which is comprised Rijndael cryptographic algorithm and HAMC-SHA-1 authentication algorithm supports the cryptographic requirements of IP AH, IP ESP, and any combination of these two protocols. Also, our IPSec cryptographic processor operates as AMBA AHB Slave. We designed IPSec cryptographic processor using Xilinx ISE 5.2i and VHDL, and implemented our design using Xilinx's FPGA Vertex XCV600E.
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This paper proposes design and implementation for IKE system that is available to IP security communication on IPv6 network. IPsec is a standard for security on network or processing layer of network communication. IPsec consists of step to negotiate security policy and step to negotiate and provide security key material for peer-to-peer security. We use the ISAKMP for negotiating security policy. And we use the IKE for negotiating and providing the key material. The system is based on VxWorks and is tested with Racoon that is a IKE daemon on FreeBSD. In this paper, we propose an implementation method for mobile host providing network communication with IP security.
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Elliptic Curve Cryptography (ECC) coprocessors support massive scalar multiplications of a point. We research the design for multi-segment multipliers in fixed-size ECC coprocessors using the multi-segment Karatsuba algorithm on GF($2^m$). ECC coprocessors of the proposed multiplier is verified on the SoC-design verification kit which embeds ALTERA EXCALIBUR FPGAs. As a result of our experiment, the multi-segment Karatsuba multiplier, which has more efficient performance about twice times than the traditional multi-segment multiplier, can be implemented as adding few H/W resources. Therefore the multi-segment Karatsuba multiplier which satisfies performance for the cryptographic algorithm, is adequate for a low cost embedded system, and is implemented in the minimum area.
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This paper proposes partial image encryption system for secure transmission of images. Partial image encryption is suitable for real-time processing purpose of multimedia data that needs compression and encryption. Compression part uses modified SPIHT algorithm and encryption part uses AES. Partial image encryption is significant reduction in encryption time in comparison with whole image encryption.
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In this study we'll deal with the small-sized metalized film capacitors with large capacity which head have
$5mm{\times}5mm{\times}2.5mm$ dimension. The lead wire is used to weld at both sides of capacitors. At that time the position gap between the welding machine and lead wire supplier would cause the welding error. Also, during the tapping processing of metalized film capacitors, the interval error among the capacitors, the length error of lead frame attached at the capacitors, and the straightness distortion of the lead frame could happen. As mentioned, four kinds of error parameters will be measured and analyzed by using the automatic visual inspection system that is implemented with CCD camera, optical parts, background lighting, and image processing algorithms. Finally we are able to achieve success rate above 99% to detect the welding faults of capacitors in the field test. -
In this study, we develop a remocon inspection automatic system using machine vision technique. By our proposed inspection system, the inspection accuracy and processing time was considerably improved.
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This paper represents 3D line segment extraction method, which can be used in generating 3D rooftop model. The core of our method is that 3D line segment is extracted by using line fitting of elevation data on 2D line coordinates of ortho-image. In order to use elevations in line fitting, the elevations should be reliable. To measure the reliability of elevation, in this paper, we employed the concept of self-consistency. We carry out the experiment of 3D line extraction using synthetic images generated from Avenches data set of Ascona aerial images.
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Stereo image analysis has been an important tool for reconstructing 3D terrain. By In its nature, occlusion is one of difficulties we cannot avoid in stereo matching. This paper presents a study on occlusion detection by employing LRC(Left-Right Check) and OCC(Occlusion Constraint). Experimental results show that these method can effectively detect occluded regions and those regions are usually occurred around object contours and scene discontinuity.
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There are no authentic solutions in a face region extraction problem though it is an important part of pattern recognition and has diverse application fields. It is not easy to develop the facial region extraction algorithm because the facial image is very sensitive according to age, sex, and illumination. In this paper, to solve these difficulties, a fuzzy color filer based on the facial region extraction algorithm is proposed. The fuzzy color filter makes the robust facial region extraction enable by modeling the skin color. Especially, it is robust in facial region extraction with various illuminations. In addition, to identify the fuzzy color filter, a linear matrix inequality(LMI) optimization method is used. Finally, the simulation result is given to confirm the superiority of the proposed algorithm.
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Conventional CDDA (Compact Disc Digital Audio) system has limitations come from sampling frequency and quantization bit, 44.1kHz and 16 bit respectively. So, new medium is developed for high-resolution audio recording, like as DVD-audio etc. But CDDA is a widely used medium for high fidelity audio yet, because new medium has complexity and difficulty in manufacturing system. In this paper, we design a new encoding system for high-resolution audio signal. The system is backward compatible with conventional CDDA. By evaluation for encoding and decoding process, we describe practicability of our proposal system.
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This paper proposes a real-time approach on the rotational motion estimation and correction for the roll stabilization of the sight system. This method first estimates a rotation center by the least-mean square algorithm based on the motion vectors of some feature points. And, then, a rotation angle is searched for a best matching block between a reference block image and seccessive input images using MPC(maximum pixel count) matching criterion. Finally, motion correction is performed by the bilinear interpolation technique. Various computer simulations show that the estimation performance is good and the proposed algorithm is a real-time implementable one to the TMS320C6415(500MHz) DSP.
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Film printing companies have many problems during a printing process. Most of all, even an insect or dirt stick to the transparent film may cause severe errors until the end of printing job, which means big economic damage to the company. To prevent some insect-dots or dirt-dots, we have to Inspect the total area of film. However, it is very difficult to inspect the film in real-time due to the high-speed of printing that usually more than 150 m/min. A hardware based approach, for example DSP-based approach can be the one of solution candidates, but the total cost and the complexity increases the very high-level. In this paper, we suggest a software based approach, using MMX technology, to inspect the film in real-time. By Many real-plant experiments, we can see the suggest approach is applicable for the inspection of food packaging film in real-time.
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Many motion object detection algorithms rely on the process of background subtraction, an important technique that is used for detecting changes from a model of the background scene. This paper propose a novel method to update the background model image of a visual surveillance system which is not stationary. In order to do this, we use a background model based on statistical qualities of monitored images and another background model that excluded motions. By comparing each changed area computed from the two background model images and current monitored image, the areas that will be updated are decided.
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This paper proposes a new classification system combining the adaptive feature weighting algorithm using the genetic algorithm and the modified KNN rule. GA is employed to choose the middle value of weights and weights of features for high performance of the system. The modified KNN rule is proposed to estimate the class of test pattern using adaptive feature space. Experiments with the unconstrained handwritten digit database of Concordia University in Canada are conducted to show the performance of the proposed method.
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This paper propose a target tracker using phase correlation. The tracker consist of a pre-processing module, a translation estimation module based on phase correlation, a fine motion estimation module applied when confidence rate could not fulfill a threshold value and a reference image update module. The fine motion estimation module measure the shift, rotation and scale of input image compared to reference using Fourier-Mellin transform. Proposed tracker was tested its accuracy and robustness using some real indoor and outdoor image sequences.
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This paper propose a new detection method of curve lane using Catmull-Rom spline for recognition various shape of the curve lane. To improve the accracy of lane detection, binarization and thinning process are firstly performed on the input image. Next, features on the curve lane such as curvature and orientation are extracted, and the control points of Catmull-Rom spline are detected to recognize the curve lane. Finally, Computer simulation results are given using a natural test image to show the efficiency of the proposed scheme.
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This paper proposes an integerized approach to solve PCA(Principal Component Analysis) feature extract procedure mainly used for the face recognition. A simple conversion to integer values has the risk to reduce the precision compared to that of the floating points operations. We integerize the PC variables by normalizing with the maximum of them, and show the efficiency of the proposed scheme by comparing the results to those of the float/double precisions. The integerized scheme is expected to be an efficient way for the real-time implementation of PCA's recognition stage, because integer operator is more desirable than floating point ones. Further research is to find a way to implement face detection and to measure the distances from the stored PCs for the full real-time face recognition.
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The current JPEG-2000 standard is a wavelet based scheme because wavelet transform have some advantages compare to DCT transform. In compressed images, there are some image degradation factors like contrast distortion by Quantization process. This factor is very important to HVS (Human Visual System). Therefore, In this paper, we propose a new algorithm for contrast enhancement using the properties of wavelet coefficients. This algorithm is processed in the wavelet domain and so it can be applied efficiently to JPEG-2000.
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In this work, we propose new method of sigma filtering for efficient filtering and preserving edge regions in DCT Domain. In block-based image compression technique, the image is first divided into non-overlapping
$8{\times}8$ blocks. Then, the two-dimensional DCT is computed for each$8{\times}8$ block. Once the DCT coefficients are obtained, they are quantized using a specific quantization table. Quantization of the DCT coefficients is a lossy process, and in this step, noise is added. In this work, we combine IDCT matrix and filter matrix to a new matrix to simplify filtering process to remove noise after IDCT in spatial domain, for each$8{\times}8$ DCT coefficient block, we determine whether this block is edge or homogeneous region. If this block is edge region, we divide this$8{\times}8$ block into four$4{\times}4$ sub-blocks, and do filtering process for sub-blocks which is homogeneous region. By this process, we can remove blocking artifacts efficiently preserving edge regions at the same time. -
In this paper, We proposed an algorithm which extraction iris region from 2D image. Our method is composed of three parts : internal boundary defection and external boundary detection. Since eyelid and eyelash cover part of the boundary and the size of iris changes continuously, it is difficult to extract iris region accurately. For the interior and exterior boundary detection, we used partial differentiation of histogram. Performance of the proposed algorithm is tested and evaluated using 360 iris image samples.
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This paper is about vision system that exhibits automatic examination of the conditions of shaft's worm. The system is composed of three part : image acquisition, vision algorithm, and user interface. The image acquisition part is composed of motor control, illumination and optics. The vision algorithm examines the parts by labeling algorithm using shaft image. User interface is divided into two parts, user interface for feature registering with control value settings and user interface for examination operation. The automatic inspection system of this research is a tool for final examination of shaft worm. This tool can be practically used in production lines with simple adjustments.
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This paper presents the system widely used for extraction of human body recognition system in the field of bio-metric identification. The Human body recognition system is used in many fields. This biological is appled to the human recognition in banking and the access control with security. The important algorithm of the identification software usese hand lines and hand shape geometry. We used the simple algorithm and recognizing the person by their hand image from the input camera. The geometrical characteristics in hand shape such as length of finger to whole hand length thickness of finger to length, etc are used.
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In this paper, we propose a low bit-rate embedded video compression scheme with 3-D block partition coding in the wavelet domain. The proposed video compression scheme includes multi-level 3-dimensional dyadic wavelet decomposition, raster scanning within each subband, formation of block, 3-D partitioning of block, and adaptive arithmetic entropy coding. Although the proposed video compression scheme is quit simple, it produces bit-stream with good features, including SNR scalability from the embedded nature. Experimental results demonstrate that the proposed video compression scheme is quit competitive to other good wavelet-based video coders in the literature.
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This paper presents a novel data transmit method using display units of mobile devices. Mobile devices such as personal-digital-assistants (PDAs) and cellular phones have a display unit. The typical display unit is a liquid-crystal-display (LCD) with an back-light. Since the proposed data transmit method uses the LCD or back-light as a data transmitter, it is a kind of sightable light communication. Tn order to transmit the data, the display unit drived by an application program on the platform of mobile devices. In this paper, detailed data transmit scheme, specific data protocol are presented and discussed. Finally, with the experimental results, usefulness of the proposed data transmit method is verified.
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This paper presents a structure of the searcher using the space diversity in array antenna system operating in the DS/CDMA signal environments. The new technique exploits the fact that the In-phase and Quadrature components of interferers can respectively be viewed as independent Gaussian noise at each antenna element in most practical CDMA (Code Division Multiple Access) signal environments. The proposed PN acquisition scheme is a single dwell serial PN acquisition system consisting of two stage, that is, the searching stage and the verification stage. The searching stage correlates the received signals with the local PN oscilator for obtaining the synchronous energy at the entire uncertainty region. The verification stage compares the searching energy with the optimal threshold, which is pre-designed in the Lock-Detector, and decides whether the acquisition is successful or fail. In this paper, we analyzed the relationship of both diversity order and the mean acquisition time. In general, It is known that the mean acquisition time decreases significantly as the number of antenna elements increases. But, the enhancement of the performance is saturated in terms of PN acquisition scheme. Therefore, to decrease the mean acquisition time, we must design the optimal array antenna system by considering the operating SNR range of the receiver, the detection probability, and the false alarm probability. The performance of the proposed acquisition scheme is analyzed in frequency-selective Rayleigh fading channels. In this paper, the effect of the number of antenna elements on acquisition scheme is considered in terms of the detection probability, false alarm probability. and the mean acquisition time.
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This paper deals with the real-time monitoring and control system using PC, PDA(Win CE embedded device) and PCS(based BREW platform). The camera attached to the server captures the moving target, and the captured frame of color image is encoded in JPEG for image compression at the server. The client(PC, PDA, PCS) receives the image data from the remote server and the received image is decoded from decompression. We use the TCP/IP protocol to send the image frames. The client can control the position of the camera by sending the control command to the server. Two DC servo motors for the camera are controlled in any directions, up-down and left-right, by the controller which is communicating with the server via the serial communication to get the control command. In this way, on the client we can monitor the moving images at the server and also control the position of the camera.
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We propose a video chatting algorithm using MPEG-4 over Mobile IPv6. This real-time system transmits video and character data based on UDP. To send data efficiently within limited bandwidth, we use a standard multimedia compression algorithm, MPEG-4, that encodes video data and mobile IPv6 guarantees effective mobility. This system presents the example of the mobile multimedia applications that will be the solution for the next internet services.
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A new method to control a remote robot with PDA and wireless network is presented. The needs of remote control systems using a home network environments are increased in these days. To solve the shortage of IP address in network, authorized TCP/IP and unauthorized TCP/IP address are used. The unauthorized TCP/IP is obtained by using MAC Address in the system and Network Layer. The model in the system is similar to Sever&Client in structure. Using this system, it is very easy to combine one network device with other network system. A robot system and PDA are used to show the effectiveness of the control system in home network environments.
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We can categorize mobility two main fields in IP environment. If Mobile IP manages macro mobility, Cellular IP deal with micro mobility. For seamless connection, it is major problem to reduce packet loss in the network layer during handoff. This paper will introduce a scheme which reduces packet loss during micro mobility which use indirect handoff mechanism in Cellular IP, and will verify the efficiency of that scheme by computer simulation.
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Hardware implemented ring buffer systems and methods are presented for the effective management of the ring buffer in TCP/IP communication. The layer interface of the ring buffer systems transfer free buffer and used buffer size information to the TCP/IP stack upper or low layer. The pointer updation interface calculates a temporary pointer from the data size which is needed by the present pointer of the ring buffer and upper or lowyer layer. The pointer manager of the ring buffer systems is responsible for saving the present pointer of the ring buffer, updating the ring buffer pointer to the new pointer, calculating the free buffer size and used buffer size of the ring buffer, and transferring the information to the upper layer. The ring buffer systems help the TCP/IP layer and TCP/IP upper or lower layer to decide the sending or receiving data size effectively. The delay of transferring data can be lowered by the ring buffer system.
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In wireless sensor networks, fair allocation of bandwidth among different nodes is one of the critical problems that effects the serviceability of the entire system. Fair bandwidth allocation mechanisms, like fair queuing, usually need to maintain state, manage buffers, and perform packet scheduling on a per flow basis, and this complexity may prevent them from being cost-effectively implemented and widely deployed. It is a very important and difficult technical issue to provide packet scheduling architecture for fairness in wireless sensor networks. In this paper, we propose an packet scheduling architecture for sensor node, called FISN (Fairness Improvement Sensor Network), that significantly reduces this implementation complexity yet still achieves approximately fair bandwidth allocations. Sensor node for sensing estimate the incoming rate of each sensor device and insert a label into each transmission packet header based on this estimate. Sensor node for forwarding maintain no per flow state; they use FIFO packet scheduling augmented by a probabilistic dropping algorithm that uses the packet labels and an estimate of the aggregate traffic at the gathering node. We present the detailed design, implementation, and evaluation of FISN using simulation. We discuss the fairness improvement and practical engineering challenges of implementing FISN in an experimental sensor network test bed based on ns-2.
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Orthogonal frequency division multiplexing(OFDM) is one of the most promising technique for next generation wireless broadband communication systems. In this paper, we propose a new bit allocation algorithm in multiuser OFDM. The proposed algorithm is derived from the geometric progression of the additional transmit power of subcarriers and the arithmetic-geometric means inequality. The simulation shows that this algorithm has similar performance to the conventional adaptive bit allocation algorithm and lower computational complexity than the existing algorithms.
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최근 무선 랜의 상용화에 따른 다양한 어플리케이션들이 제공되고 있다. 이 중 대용량 멀티미디어 트래픽을 사용한 다양한 서비스가 제공되고 있는데, 이들에 대한 QoS 보장을 위한 다양한 기법들이 세안되고 있다. 기존의 802.11에서는 CSDP 스케줄러를 이용하여 각각의 MH로 보내지는 데이터에 대한 QoS를 보장하기 위해 노력하였고, WG(Working Group) e가 만들어지면서 보다 상세하게 데이터 트래픽에 대한 QoS를 더 연구하게 되었다. 본 논문에서 제안하고자 하는 스케줄러는 IEEE 802.11에 CSDP (Channel State Dependent Packet) 스케줄러의 LSM(Link State Monitoring)의 개념과 IEEE 802.11e에서 제안하고 있는 EDCA (Enhanced Distributed Channel Access)방식과 HCCA (HCF Controlled Channel Access) 방식이 결합되어 있는 스케줄러에 실제 스케줄링이 이루어지는 PHY Queue에 가기 전 대기하는 Queue에 가상 큐를 적용하여 트레픽 특성을 고려하고, bad가 발생하는 링크로 가는 트래픽에 대해서는 임시 큐에 저장한 후에 링크가 good 상태가 되면 전송함으로써 보다 높은 QoS를 제공하며, 전체 시스템의 효율을 향상시키는 스케줄러를 제안하고자 한다.
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A sensor networkis composed of a large number of sensor nodes, which are densely deployed either inside the phenomenon or very close to it. One of the most important constraints on sensor nodes is the low power consumption requirement. Sensor nodes carry limited, generally irreplaceable, power sources. Therefore, while traditional networks aim to achieve high quality of service (QoS) provisions, sensor network protocols must focus primarily on power conservation. This paper presents the characteristics of energy consuming, average delay in 802.11 MAC, S-MAC that is specifically designed for wireless sensor networks. We analyze the energy consuming state in the 802.11 MAC in the simulation topology nodes, and measure average delay in 802.11 and S-MAC. Energy efficiency is the primary goal in this protocol design. 802.11 MAC is more efficient than S-MAC in the average delay, throughput. However S-MAC is an energy efficient protocol, a tradeoff between energy efficiency and delay.
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ZigBee Alliance is a network designed for low-cost and very low-power short-range wireless communications. The ZigBee Alliance is a consortium formed by several leading semiconductor and industrial manufactures, and end users. One of the tasks of this organization is the definition of the networking support and applications profiles that will use IEEE Std 802.15.4-compliant transceivers. In the case of IEEE Std 802.15.4, the ZigBee Alliance is an organization that has led the development of the upper layers, through the definition of application profiles. We have implemented ZigBee home control system, however we have not fully implemented. Because of the ZigBee is not perfectly standarded. We will have to implement according to ZigBee Specifications.
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Queuing is waiting lines which play routing service when packet entered. Queuing is decide how and whom is going to provide priority service. This is kind of first in first out(FIFO) or weighted fair queuing(WFQ) method. In this study, UDP design using WFQ way to serve to provide service evenly and rapidly in network. Also in actuality internet, datagram analyzed by packet captured. Queuing services through the requesting port number, input, output, output queuing creation & delete, message request by internet control message protocol(ICMP). Queuing designed in control block module, input queues, input/output module composition. In conclusion, I have confirm queuing result of WFQ method by the datagram information analyzed.
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Transmission control protocol(TCP) is protocol used in internet. TCP is seldom transmission error and is protocol based on wire environment. TCP uses 3 way handshake ways, data transmission control through windows size, data transmission control through reception confirmation, sliding window for packet delivery. In this study, designed TCP packet ion module for analyze the TCP segments & correct information about TCP. TCP capture in internet using designed TCP module and analysed TCP segments composition. Through this, could analyze the correct information of protocol in network.
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Wireless LAN Voice over IP(VoIP) equipment needs Quality-of-Service(QoS) with priority for processing real-time traffic. This paper shows transmit function implementation of wireless LAN(WLANs) media access control(MAC) support VoIP, and it has an advantage of guarantee of QoS and is adaptable to VoIP or mobile wireless equipment. The IEEE 802.11e standard in progress has four queues according to four access categories(AC) for transmit and the MAC transmits the data based on EDCA. The value of AC is from AC0 to AC3 and AC3 has the highest priority. The transmit method implemented at this paper ensure QoS using one transmit FIFO in hardware since real-time traffic data and non real-time traffic data has the different priority. The device driver classifies real-time data and non real-time data and transmit data to hardware with information about data type. The hardware conducts shorter backoff and selects faster AIFS slot for real-time data than it for non real-time data. Therefor It make give the real-time traffic data faster channel access chance than non real-time data and enhances QoS.
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A channel allocation algorithm of multi-user OFDM(orthogonal frequency division multiplexing) system is presented. The proposed algorithm is to reduce the complexity of the system, using the GNN(gradual neural network) with gradual expansion scheme and the algorithm attempts to allocate channel with good channel gain to each user. The method has lower computational complexity and less iteration than other algorithms.
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This paper proposes design and implementation for Seamless Handoff method between adapters in a system environment where both wired and wireless adapters are present First of all, by settingLayer 2 address of wired adapter to Layer 2address of wireless adapter, then generate virtual adapter on the above layer to make these two adapters operate on an IP address. Under the condition, when wired communication via the wired adapter gets disconnected while in service, wireless handoff occurs by mapping information on the wireless adapter to the virtual adapter. According to the method proposed in this paper, continuous session can be obtained even when handoff between wired and wireless adapters occurs at lower level in an application where both IP address and Port address are used to maintain session since If address does not change.
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In this paper, we propose an optimal power control algorithm for CDMA cellular systems. The proposed power control algorithm is based on linear quadratic control theory. As the cellular system includes the changeability of system environment or various noise, Kalman filter is adapted to estimate the time-varying interference. This is the well-known linear quadratic Gaussian (LQG) theory. Through this algorithm, power transmission of each mobile with optimal one is more realistic. Simulation results show a fast convergence rate to optimal power value, and a rapid decreasing outage probability.
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In this paper, we analyses transmission performance of interleaving for cipher communication in TDMA STD DP mode of aerial tactical communication link. In LINK16 link we present about transmission architecture of STD DP mode and study an effect of interleaving, the capability of crypto synchronization pattern, and a quality of degraded effect of transmission communication during crypto communication.
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This paper proposes a common platform for an internet-based mobile robot and its operator terminal. The common platform can reduce the cost and time to develop an internet-based robot and its operator terminal. The robot performs the role of a server and its terminal a client. One operator can use this terminal to make a command and this command can be sent to the robot through a wireless network. According to given commands, the robot moves a point and sends an image by using a camera or desired information by using other sensors. The information sent from the robot can help an operator to control the robot. The mobile robot consists of two modules, main module and motion module. Main module can exchange information with the operator terminal, process information, and send a command to motion module. Each application program for one internet-based mobile robot and its operator terminal will be developed to show that the same platform can be used for them. Also, it will be shown that the robot can be controlled easily by using its operator terminal.
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The study for ubiquitous computing infra is proceeding actively, it make possible to use service and access network anywhere, anytime because of wire/wireless communication technology and progress of hardware. Domestically, study for the network mobility support technology which is the key technology for future ubiquitous computing realization have progressed, but that is insufficient. Especially, there is no study for independent mobility support study about railway wireless network. So, this study propose network mobility management technology for mobile network infra in railway and proper network model in train.
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The Controller Area Network (CAN) is being widely used in real-time control applications such as automobiles, aircraft, and automated factories. Unfortunately, CAN, in its current form, is not able to either share out the system bandwidth among the different devices fairly or to grant an upper bound on the transmission times experienced by the nodes connected to the communication medium as it happens, for instance, in the token-based networks. In this paper, we present An Application Layer Design for Humanoid Robot in the CAN. Besides introducing the new algorithm, this paper also presents some performance figures obtained using a specially developed software simulator and experimentation for composition of CAN which uses JTAG mode of a parallel debugging., while the behavior of the new algorithm is compared with the traditional CAN systems. in order to see how effective they are.
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In this paper, we identify the memory effect of high power(125W) laterally diffused metal oxide-semiconductor(LDMOS) RF Power Amplifier(PA) by two tone IMD measurement. We measure two tone IMD by changing the tone spacing and the power level. Different asymmetric IMD is founded at different center frequency measurements. We propose the Tapped Delay Line-Neural Network(TDNN) technique as the modeling method of LDMOS PA based on two tone IMD data. TDNN's modeling accuracy is highly reasonable compared to the memoryless adaptive modeling method.
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A blind separation problem in a multiple-input-multiple-output (MIMO) linear time-invariant (LTI) system with finite-alphabet inputs is considered. A discrete-time matrix equation model is used to describe the input-output relation of the system in order to make full use of the advantages of modern digital signal processing techniques. At first, ambiguity problem is investigated. Then, based on the results of the investigation, a new identifiability condition is proposed for the case of an input-data set which is widely used in digital communication. A probability bound such that an arbitrary input matrix satisfies the identifiability condition is derived. Finally, Monte-Carlo simulation is performed to demonstrate the validity of our suggestions.
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There are various researches on MPEG techniques. MPEG technique is used to digital TV(DTV) and internet image communication. Connection method between server and client is usually using wire. Applications may be expanded, if wireless technology is used between server and client system. In this paper, Bluetooth is used for connection method between server and client. Bluetooth offers fast and reliable transmissions of both voice and data over the globally available 2.4GHz ISM (Industrial, Scientific and Medical) band. One of the major application purposes of Bluetooth is the cable replacement for mobile and peripheral devices. Bluetooth has the advantage of small size, low power and low cost. It has the disadvantage of limited bandwidth and limited range. In order to transfer effectively image Information between server and client using Bluetooth, we apply MPEG-2 and MPEG-4 image compression techniques and the results are compared with each other.
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최근 홈네트워크와 관련된 기술 및 산업이 확대되고 있는 것은 인터넷을 비롯한 다양한 인프라 망의 구축을 근간으로 하고 있다. 현재 홈네트워크 관련 산업은 소비자가 필요로 하는 핵심 응용 서비스를 제공할 수 있는 제품을 시장에 내 놓을 수 있을 것인가와 이를 위하여 필요한 기술을 개발하는 것이 무엇보다 중요한 시점에 있다. 따라서 국내 홈네트워크 시장진화 전망, 서비스측면을 고려한 최적 대안, 주택유형을 고려한 최적대안 등을 도출함으로써 국내 홈네트워크 기술의 선결요인과 상황에 따른 고려요인을 제시하였다. 그리고 이러한 선결요인과 함께 상황에 따른 고려요인을 토대로 국내 홈네트워크 기술의 최적대안을 살펴보았다.
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홈네트워크를 구현해 가정에 서비스를 전달하기 위해서는 가정내의 홈네트워크 환경, 서비스를 가정까지 전달해주는 외부의 네트워크 환경, 그리고 다양한 서비스 및 콘텐츠의 제공 둥이 필요하다. 다양한 통신망의 변혁 속에서 홈네트워크는 이용자가 직접 통신망에 접속하여 각종 통신망 서비스를 이용하는 정보인프라의 최종단으로 위치하고, 사람의 순환계에 있어서 실핏줄과 같은 역할을 담당하는 부분이며, 홈게이트웨이는 이를 투명하게 전달, 중재하는 핵심역할을 담당한다. 따라서 홈게이트웨이 기능의 변화, 시장 전개 시나리오와 서비스 발전에 따른 홈게이트웨이의 진화 전망을 통하여 홈게이트웨이 업체의 주도권 전망을 분석하였다.
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In this paper, we propose an channel estimation method for Multi-Input Multi-Output-Orthogonal frequency Division Multiplexing (MIMO-OFDM). The proposed method estimates uniquely all channel frequency responses needed in space-frequency block coded OFDM systems using "comb-type" pilot symbols. To reduce the computational complexity of the proposed method, least square(LS) and linear minimum mean square error(LMMSE) are used in the frequency-domain. The performance of the proposed approach is evaluated by computer simulation for rayleigh fading channel.
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우리나라의 디지털 방송환경은 지상파와 위성에서는 빠른 진전을 보이고 있는 반면, 케이블방송에서는 너무나도 느린 진전을 보이고 있다. 무엇보다도 지상과 위성방송에서는 이미 HD 고화질 방송서비스를 실시하고 있지만, 케이블방송에서는 아직까지도 HD셋탑박스의 부재로 시범서비스조차 할 수 없는 실정이다. 이에 본 논문에서는 국내 디지털케이블방송의 표준인 OpenCable에 맞추어 HD방송 및 CableCard지원에 대한 내용을 구현위주로 기술한다.
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본 논문의 목표는 일체형 디지털 TV에서 디지털 방송 수신과 방송 컨텐츠를 녹화, 저장, 재생이 가능할 뿐만 아니라 조만간 시작될 데이터 방송을 수신할 수 있는 내장형 디지털 방송수신 및 개인 비디오 저장 시스템 Platform 개발이다. 디지털 방송과 데이터방송 수신이 가능한 Set-Top Box 기능, 수신된 방송의 저장 및 재생이 가능한 PVR 기능을 지원할 수 있는 시스템의 구조를 설계하였다. 고품질 디지털 방송 서비스가 본격적으로 시작됨에 따라 디지털 방송 수신기와 PVR 기능이 복합된 제품의 수요가 증가할 것으로 예상되며 이러한 고성능 복합시스템은 필수적일 것이다. 이러한 기능을 수행하기 위하여 시스템 제어를 위한 CPU로는 PMC-Sierra 사의 MIPS Architecture에 기반을 둔 RM5231을 채택하고, Teralogic 사의 TL811 System Controller을 채택하여 시스템을 이루고 있는 각종 디바이스를 구성하고, MPEG-2 Demux/Decoding을 위해 Teralogic TL851 Graphics & Display Processor을 채택하였다. 개발된 시스템을 테스트하기 위하여 현재 각 방송사들의 시험 방송을 수신하고 PVR 기능을 테스트하였다.
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Networked Digital Recorder(NDR) Platform is a system that owns contents jointly between tv viewers connected by the broadcast broadband convergence network. NDR suggests a new content distribution chain model that users can receive broadcast contents, share contents and sends contents by convergence network. This paper looks at the system requirements, service model and the overall system architecture of NDR platform.
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Semantic video object extraction is important for tracking meaningful objects in video and object-based video coding. We propose a fast semiautomatic video object extraction algorithm which combines a watershed segmentation schemes and chamfer distance transform. Initial object boundaries in the first frame are defined by a human before the tracking, and fast video object tracking can be achieved by tracking only motion-detected regions in a video frame. Experimental results shows that the boundaries of tracking video object arc close to real video object boundaries and the proposed algorithm is promising in terms of speed.
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In this paper, we explore the streaming environment which adopts the MPEG-4 FGS(Fine Granualarity Scalability) encoding schemes. We investigate the server and client structure to fine the bottleneck of streaming system. After the structures, we propose a novel packet scheduling algorithm which enhances user perceptable playback quality. Experimental results show the performance enhancement of our algorithm, and system require less resources.
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In the decoding process of interframe wavelet coding, the inverse wavelet transform requires huge computational complexity. However, the decoder may need to be used in various devices such as PDAs, notebooks, PCs or set-top Boxes. Therefore, the decoder's complexity should be adapted to the processor's computational power. A decoder designed in accordance with the processor's computational power would provide optimal services for such devices. So, it is natural that the complexity scalability and the low complexity codec are also listed in the requirements for scalable video coding. In this contribution, we develop a method of controlling and lowering the complexity of the spatial wavelet transform while sustaining almost the same coding efficiency as the conventional spatial wavelet transform. In addition, the proposed method may alleviate the ringing effect for certain video data.
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In this work, we develop on-line traffic prediction algorithm for real-time VBR traffic. There are a number of important issues: (i) The traffic prediction algorithm should exploit the stochastic characteristics of the underlying traffic and (ii) it should quickly adapt to structural changes in underlying traffic. GOP ARIMA model effectively addresses this issues and it is used as basis in our bandwidth prediction. Our prediction model deploy Kalman filter to incorporate the prediction error for the next prediction round. We examine the performance of GOP ARIMA based prediction with linear prediction with LMS and double exponential smoothing. The proposed prediction algorithm exhibits superior performam againt the rest.
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With the developing of current multimedia broadcasting, user will be provided for lots of various content through the various channel and media. Content provider and consumer want the various service using content with the better quality which is fit to users' preference. For transmitting this content in the limited transmission channel capacity, it needs to transmit the highly compressed content. The content of 3D mesh model-based on MPEG-4 enables the various content service that provides the lower size and the resonable quality, and Personalize(Targeting) service just provide the contents that user more wants and likes. This paper presents the study on the targeting service using compression of 3D mesh model-based on MPEG-4 and the adaptation of Embedded Graphic application program using it.
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In this study, we have evaluated and classified arthritic pathology using the auscultation of knee joint sound. Six normal persons and 11 patients with knee problem were enrolled. Six patients of Group 1 needed an orthopeadic surgery because of the ruptured wounds of meniscus or ACL(Anterior Cruciate Ligament) and 5 patients of Group 2 diagnosed as osteoarthritis. Subjects were taken knee flexion and extension being seated in a chair for 20 seconds which repeated 3 times. Also subjects stood up and sit down repeatedly in the same way. After the movement of knee was divided into 18 degrees, the pitch perturbation according to partial degrees was analyzed and the DTW(Dynamic Time Warping) method was applied for normalizing a time-axis and unpaired t-test was used for statistic results among groups. As a result, the amplitude and frequency perturbations of group 2 was higher than group 1(p<0.05) and showed a characteristic 'w-shape' in angle-amplitude graph. These results suggest that the analysis of knee joint sound might assist in early diagnosis of knee joint disease.
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Kim, Keo-Sik;Yoon, Dae-Young;Lee, Myung-Gwon;Song, Chang-Hun;Kim, Ji-Sun;Park, Seong-Su;Kim, Jong-Jin;Kim, Ji-Hun;Lee, Gil-Seong;Lee, Min-Hee;Chae, Min-Su;Kim, Min-Ju;Song, Chul-Gyu 310
The aim of this study was to analyze the characteristics of knee joint sound in frequency domain and classify the knee joint diseases. The spectral analysis of knee joint sounds was performed using LPC(Linear Predictive Coding) and Wigner-Ville distribution. Ten normal subjects and 5 patients with meniscal tearing were enrolled. Each subject was seated on a chair and underwent active knee flexion and extension for 60 seconds. Sampling frequency was 10kHz and electronic stethoscope and electro-goniometer were applied during the knee motion for data collection. The spectral analysis showed 3 peaks in both groups and the difference energy distribution in time-frequency domain. These results suggest that the diagnosis of knee joint pathology using the auscultation could be easier and more correct. -
Yoon, Dae-Young;Kim, Keo-Sik;Seo, Jeong-Hwan;Kim, Kyeong-Seop;Song, Chul-Gyu;Yang, Young-Kwang;Lee, Sang-Ok 313
Urodynamic study system is widely used for neurogenic bladder patients in various clinical setting. Generally they include 2 pressure sensors from bladder and rectum, and 1 EMG sensor. The rectal pressure catheter is often the source of data error because of gas passage and the fall out of the catheter from anus, and source of discomfort in ambulatory urodynamic system. This study is to design and calibrate the ambulatory digital urodynamic study system that can discard the rectal pressure catheter, which can make patients more comfortable and doctors can get more physiologic data. As a first step, we compared our new system with Dantec$Duet^{(r)}$ urodynamic system (Dantec, Denmark) and wanted to see the possibility of our new system. -
In this study, the influence of electromagnetic wave effected on human body of light sensing was classified. Subjects of the eye was stimulated by the rays of LED and the measured electrical signals(EEG, EOG and ERG) in human body were compared and analyzed in the case of exposed at electromagnetic wave or not. The result show that when the subjects were not exposed at electromagnetic wave, the ratio of a wave has a large percentage in the EEG signal and the ratio of
$\beta$ wave has come to good. -
The average glandular dose (AGD) is determined by the breast entrance skin exposure, x-ray tube target material, beam quality (half-value layer), breast thickness, and breast composition. Almost breast cancer always arises in glandular breast tissue. As a result, the average radiation absorbed dose to glandular tissue is the preferred measure of the radiation risk associated with mammography. If the normalized average glandular dose is known, the average glandular dose can be computed from the product of the normalized average glandular dose and breast entrance skin exposure. In this study, AGD was calculated by the breast thickness and various x-ray energy (HVL) in 50% glandular 50% adipose breast by Mo.-Rh. assembly. AGD is 84 mrad in compressed 5 cm breast. These results show that as increasing the breast thickness, dose also increases. But as increasing the x-ray tube voltage, dose decreases because of high penetrating ratio through the object. But high tube voltage is reducing the subject contrast. From this result, we have to consider the trade-off between subject contrast of image and dose to the patient and choose proper x-ray energy range.
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Up to the present, digital replantation patients has appealed different symptoms due to blood circulatory failure. But, the level of blood circulatory failure has been evaluated only by clinical symptoms, or angiography. According to the cases of digit replantation is increasing, then objective evaluation methods of the level of blood circulation failure is needed other than patient's subjective symptoms and complaints. Although angiography, doppler, electromagnetic flowmeter, laser blood flowmeter, mechanical blood flowmeter has been used for the evaluation of the blood circulatory failure, the result was affected by time, place, surrounding temperature, patient's body temperature, and even emotion. Therefore, it is pointed out with lack of availability, feasibility and reproducibility. Thus, we compared digital blood flow of dominant hand to non dominant hand, and replanted fingers to opposite normal fingers from developed photo-plethysmography. The average digital blood flow showed no difference in normal digits each other, but, replanted digits showed average of 53% (9 - 100 %) compare to opposit normal digits. As it measure relative blood flow for circulatory failure of tissue such as fingers and toes more sensitively, reliably. In conclusion, it is expected that photo- plethysmography will be very useful for diagnosis, curative effect, prognosis of blood circulatory failure in digital replantation patient.
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ECG limb lead II signal widely used to diagnosis heart diseases and it is essential to detect ECG events (onsets, offsets and peaks of the QRS complex P wave and T wave) and extract them from ECG signal for heart diseases diagnoses. However, it is very difficult to develop standardized feature extraction formulas since ECG signals are varying on patients and disease types. In this paper, simple feature extraction method from normal and abnormal types of ECG signals is proposed. As a signal features, heart rate, PR interval, QRS interval, QT interval, interval between S wave and baseline, and T wave types are extracted. To show the validity of proposed method, Right Bundle Branch Block (RBBB), Left Bundle Branch Block (LBBB), Sinus Bradycardia, and Sinus Tachycardia data from MIT-BIH arrhythmia database are used for feature extraction and the extraction results showed higher extraction capability compare to conventional formula based extraction method.
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In this paper, ECG based cardiac disease diagnosis models are developed. Conventionally, ECG monitoring equipments can only measure and store ECG signals and they always require medical doctor's diagnosis actions which are not desirable for continuous ambulatory monitoring and diagnosis healthcare systems. In this paper, two kinds of neural based self cardiac disease diagnosis engines are developed and tested for four kinds of diseases, sinus bradycardia, sinus tachycardia, left bundle branch block and right bundle branch block. For diagnosis engines, error backpropagation neural network (BP) and probabilistic neural network (PNN) were applied. Five signal features including heart rate, QRS interval, PR interval, QT interval, and T wave types were selected for diagnosis characteristics. To show the validity of proposed diagnosis engine, MIT-BIH database were used to test. Test results showed that BP based diagnosis engine has 71% of diagnosis accuracy which is superior to accuracy of PNN based diagnosis engine. However, PNN based diagnosis engine showed superior diagnosis accuracy for complex-disease diagnoses than BP based diagnosis engine.
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In this study, we implement the multiple frequency bioelectrical impedance analysis system for body composition analysis. Overall system consists of : 1) conductivity electrodes to contact with hands and foots, 2) multiple frequency alternating current signal generator for generating 5, 50, 250kHz frequency and 800uA contained alternating current signal, 3) voltage signal detector, 4) phase signal detector, 5) key-pad to input individual information, 6) micro controller for data processing, 7) LCD for processed data to display, 8) system power, We explain the architecture of the system and required theory to implement the system. Finally, experimental results are illustrated to show the performance of the system.
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The postprocessing of fingerprint images is widely used in the elimination of the false minutiae caused by skeletonization. This paper presents the images were duplicated by The SOFM. And this Method showed that the good performance of eliminating false minutiae and fast processing.
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Genetically Optimized Fuzzy Polynomial Neural Networks Model and Its Application to Software ProcessIn this paper, we discuss optimal design of Fuzzy Polynomial Neural Networks by means of Genetic Algorithms(GAs). Proceeding the layer, this model creates the optimal network architecture through the selection and the elimination of nodes by itself. So, there is characteristic of flexibility. We use a triangle and a Gaussian-like membership function in premise part of rules and design the consequent structure by constant and regression polynomial (linear, quadratic and modified quadratic) function between input and output variables. GAs is applied to improve the performance with optimal input variables and number of input variables and order. To evaluate the performance of the GAs-based FPNNs, the models are experimented with the use of Medical Imaging System(MIS) data.
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In this paper, we introduce a new category of fuzzy inference systems baled on information granulation to carry out the model identification of complex and nonlinear systems. Informal speaking, information granules are viewed as linked collections of objects(data, in particular) drawn together by the criteria of proximity, similarity, or functionality. Granulation of information with the aid of Hard C-Means(HCM) clustering algorithm help determine the initial parameters of fuzzy model such as the initial apexes of the membership functions and the initial values of polyminial functions being used in the premise and consequence part of the fuzzy rules. And the initial parameters are tuned effectively with the aid of the genetic algorithms(GAs) and the least square method. The proposed model is contrasted with the performance of the conventional fuzzy models in the literature.
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We propose a new category of fuzzy set-based fuzzy inference systems based on data granulation related to fuzzy space division for each variables. Data granules are viewed as linked collections of objects(data, in particular) drawn together by the criteria of proximity, similarity, or functionality. Granulation of data with the aid of Hard C-Means(HCM) clustering algorithm help determine the initial parameters of fuzzy model such as the initial apexes of the membership functions and the initial values of polyminial functions being used in the premise and consequence part of the fuzzy rules. And the initial parameters are tuned effectively with the aid of the genetic algorithms(GAs) and the least square method. Numerical example is included to evaluate the performance of the proposed model.
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In this rarer, we introduce a new Fuzzy Polynomial Neural Networks (FPNNs)-like structure whose neuron is based on the Fuzzy Set-based Fuzzy Inference System (FS-FIS) and is different from that of FPNNs based on the Fuzzy relation-based Fuzzy Inference System (FR-FIS) and discuss the ability of the new FPNNs-like structurenamed Fuzzy Set-based Polynomial Neural Networks (FSPNN). The premise parts of their fuzzy rules are not identical, while the consequent parts of the both Networks (such as FPNN and FSPNN) are identical. This difference results from the angle of a viewpoint of partition of input space of system. In other word, from a point of view of FS-FIS, the input variables are mutually independent under input space of system, while from a viewpoint of FR-FIS they are related each other. In considering the structures of FPNN-like networks such as FPNN and FSPNN, they are almost similar. Therefore they have the same shortcomings as well as the same virtues on structural side. The proposed design procedure for networks' architecture involves the selection of appropriate nodes with specific local characteristics such as the number of input variables, the order of the polynomial that is constant, linear, quadratic, or modified quadratic functions being viewed as the consequent part of fuzzy rules, and a collection of the specific subset of input variables. On the parameter optimization phase, we adopt Information Granulation (IG) based on HCM clustering algorithm and a standard least square method-based learning. Through the consecutive process of such structural and parametric optimization, an optimized and flexible fuzzy neural network is generated in a dynamic fashion. To evaluate the performance of the genetically optimized FSPNN (gFSPNN), the model is experimented with using gas furnace process dataset.
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The classical dynamic backpropagation learning algorithm has the problems of learning speed and the determine of learning parameter. The Extend Kalman Filter(EKF) is used effectively for a state estimation method for a non linear dynamic system. This paper presents a learning algorithm using Dual Extended Kalman Filter(DEKF) for Fully Recurrent Neural Network(FRNN). This DEKF learning algorithm gives the minimum variance estimate of the weights and the hidden outputs. The proposed DEKF learning algorithm is applied to the system identification of a nonlinear SISO system and compared with dynamic backpropagation learning algorithm.
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In this paper, a parallel fuzzy controller for one degree of freedom magnetic levitation is designed and its performance is compared with the performance of a PID controller. Input, output scaling factor of fuzzy controller and gain of PID controller were tuned using the GA algorithm. The designed controllers are validated by numerical simulations. So it's shown that parallel fuzzy controller can give the better performance for the plant than PID controller.
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In this paper, to calculate accurate remaining volume, it presents how to figure out nickel-cadmium battery algorithm. A nickel-cadmium battery has widely been used in industrial field and to military. Recent high demands on the battery caused 'How to calculate accurate remaining volume is very important task to be solved. In this paper, it says it is useful using the terminal voltage change of the resistance that can be connected with the battery and the differentiation of the terminal voltage to calculate remaining volume of nickel-cadmium battery. And these can be used for volume inference data so that it is fuzzy based system which can be helpful to inference the remaining volume by the resistance of terminal voltage change. Because of electrochemical complexity, the volume calculating system is inferencing undirectly by experimentally built DB where as current the existing volume models are suffering to be adapted.
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The digital images contain a significant amount of redundancy and require a large amount of data for their storage and transmission. Therefore, the image compression is necessary to treat digital images efficiently. The goal of image compression is to reduce the number of bits required for their representation. The image compression can reduce the size of image data using contractive mapping of original image. Among the compression methods, the mapping is affine transformation to find the block(called range block) which is the most similar to the original image. In this paper, we applied the neural network(SOM) in encoding. In order to improve the performance of image compression, we intend to reduce the similarities and unnecesaries comparing with the originals in the codebook. In standard image coding, the affine transform is performed with eight isometries that used to approximate domain blocks to range blocks.
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시간 및 주파수 특성 분석이 용이한 웨이블릿을 신경회로망에 적용시킨 웨이블릿 신경 회로망의 파라미터 학습 방법에는 오차 역전파 알고리듬 및 유선 알고리듬 등 여러 가지 방법이 있으나 이러한 학습 방법들은 수렴 시간이 오래 걸리는 단점을 가진다. 따라서 본 논문에서는 웨이블릿 신경 회로망의 최적 파라미터를 결정하기 위한 학습 방법으로 일반적으로 비선형 시스템 추정에 주로 사용되는 확장 칼만 필터 알고리듬을 적용한 신경회로망을 제안한다. 또한 제안된 학습 알고리듬을 이용한 웨이블릿 신경 회로망으로 간접 적응 제어기를 설계하여 연속 시간 혼돈 시스템인 Duffing 시스템의 제어에 적용함으로써 확장 칼만 필터 학습 알고리듬을 적용한 웨이블릿 신경 회로망 모델의 우수성을 보인다.
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WDR(Wide Dynamic Range) camera has been recently introduced to provide good detailed information for the extremely dark or white area. The double shuttering camera acquires two pictures with different exposure time for the same scenes so that each image has its unique information as for the bright/dark area. Those images are combined internally to produce an image with enough details. This paper proposes a NN based method to control the exposure time of the WDR camera. Our goal is to develop a method to automatically control the exposure time like human decision. A neural model is trained to determine to increase/decrease shutter time for the given situation. The ability to adapt to unknown situation is shown for the sample cases.
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In this paper we propose an effective and reliable hand detection method using neural network with ICA(Independent Component Analysis) Features. Many algorithms of hand detection have been proposed yet. Among them, ICA is the one of the interesting topics in image processing. ICA can not only separate mixed signals but also efficiently extract low-dimensional features in signals. ICA features are able to represent the characteristic of the images well. The object of this paper is to use effectively ICA that has above advantage. That is, by the proper number of Independent component the arithmetic speed is faster and by normalization of ICA feature the performance of detection is more reliable. For this, we adopt the algorithm, the Proportion of variance, which select the ICA feature by comparing the ratio of variance of ICA feature. By this method, we can extract the feature that is good at classifying hand and non-hand. Our experimental results show that by using ICA features, we obtained a better performance in hand detection than by only training NN on the image. And we can use hand detection system effectively and reliably by our proposal.
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This paper addresses the wavelet-based fuzzy PI/PD controller design using DNA coding method. A structure of fuzzy controller model is adopted as the wavelet transform of which the coefficients are identified. The proposed method overcomes some mathematical limits of conventional methods by using the fuzzy logic that is optimized by DNA coding method. The feasibility of the proposed fuzzy controller design scheme is verified by applying to the servo control of the optical disk drive.
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The SRM is more robust and lower cost than other type motors. The inverter for SRM cannot have shoot through fault, since a phase winding of SRM is independent of other phase windings. The SRM has high starting torque and high power density. But it has torque ripples due to nonlinear magnetic characteristics. Therefore, SRM has highly non-linear torque producing characteristics. Because fuzzy logic is a flexible and general-purposed method for implementing non-linear dynamic functions, it is effective for the control of high current SRM. We design the fuzzy controller and demonstrate the fuzzy control system by MATLAB.
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Genetic algorithm was motivated by biological evaluation and has been applied to many industrial applications as a powerful tool for mathematical optimizations. In this paper, a new genetic optimization algorithm is proposed. The proposed method is based on Mendel's law, especially dominance and recessive property. Homologous chromosomes are introduced to implement dominance and recessive property compared with the standard genetic algorithm. Because of this property of suggested genetic algorithm, homologous chromosomes looks like the chromosomes for the standard genetic algorithm, so we can use most of existing genetic operations with little effort. This suggested method searches the larger solution area with the less probability of the premature convergence than the standard genetic algorithm.
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In this paper, a robust
$H_{\infty}$ stabilization problem to a uncertain fuzzy systems with time-varying delay via static output feedback is investigated. The Takagi-Sugeno (T-S) fuzzy model is employed to represent an uncertain nonlinear systems with time-varying delayed state. Using a single Lyapunov function, the globally asymptotic stability and disturbance attenuation of the closed-loop fuzzy control system are discussed. Sufficient conditions for the existence of robust$H_{\infty}$ controllers are given in terms of linear matrix inequalities. -
In this parer, we propose a clustering that perform algorithm using new convergence properties. For detection and optimization of cluster, we use to similarity measure with cumulative probability and to inference the its parameters with MLE. A merits of using the cumulative probability in our method is very effectiveness that robust to noise or unnecessary data for inference the parameters. And we adopt similarity threshold to converge the number of cluster that is enable to past convergence and delete the other influence for this learning algorithm. In the simulation, we show effectiveness of our algorithm for convergence and optimization of cluster in riven data set.
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In this paper, we have designed a fingerprint cognition system based on the embedded Linux. The proposed algorithm in this paper use the wavelet transform to derive the special feature vector from the captured fingerprint and a probabilistic neural network is used to compare the feature vectors for the fingerprints. The system consists of server PC based on the Linux and the client based on the embedded Linux. The client is a Tynux box-x board using the PXA-255 CPU. For the acquisition of the fingerprint image, we use d the AS-S2 semiconductor sensor. The system is likely to be used to develop a police inspection system.
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In this paper, we performed the implementation of image transmission server system using embedded system that is for the specified object and easy to install at any places and move to wherever. Since the embedded system has lower capability than PC, we have to reduce the quantity of calculation and transmission. The image compression like JPEG, needs that the server calculates for making compressed image, makes the server carry the load. So we compresses the image at the server and transmit the codes to the clients connected, then the received codes from server are decoded and displayed at the clients. In this process to make the image compression and transmission effectively, we decrease the procedure as simple as possible to transmit the data in almost real-time. We used the Redhat linux 9.0 OS at the host PC and the target board based on embedded linux. The image sequences are obtained from the camera attached to the FPGA board with ALTERA chip. For effectiveness and avoiding some constraints, we made the device driver. Generally the image transmission server is PC, but using the embedded system as a server makes the server portable and cheaper than the system based on PC.
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Park, Joo-Hyun;Ryu, Seong-Min;Jang, Myung-Soo;Choi, Sea-Hawon;Choi, Kyu-Myung;Cho, Jun-Dong;Kong, Jeong-Taek 391
For performance and stability of a synchronized system, we need an efficient Clock Tree Synthesis(CTS) methodology to design clock distribution networks. In a system-on-a-chip(SOC) design environment, CTS effectively distributes clock signals from clock sources to synchronized points on layout design. In this paper, we suggest the pre-layout analysis of the clock network including gated clock, multiple clock, and test mode CTS optimization. This analysis can help to avoid design failure with potential CTS problems from logic designers and supply layout constraints so as to get an optimal clock distribution network. Our new design flow including pre-layout CTS analysis and structural violation checking also contributes to reduce design time significantly. -
CE 제품에 리얼타임 OS를 도입하면서, 제품의 조건을 만족시키기 위한 기술에 대해 많은 연구가 진행되고 있다. 특히, CE 제품에 있어서 중요한 이슈인 부팅 시간은 펌웨어수준과 비교했을 때 코드사이즈나 OS 초기화 과정 때문에 다소 느려지는 경향을 보이고 있다. 본 논문은 이러한 CE 제품의 부팅 시간에 초점을 맞추고 리얼타임 OS 적용시의 부팅 시간을 개선하였다. 구현에 사용된 ARM920T Core는 32-비트 RISC 구조이며, 각 16KB의 인스트럭션 Cache와 데이터 Cache, 그리고 MMU(Memory Management Unit)로 구성되어 있으며, 리얼타임 OS는 선점형 방식의 커널로 구성된 OS를 사용하였다.
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Generally microkernel has properties of Portability, reusability and scalability. In particular microkernel technique has been applied to development of real time kernel on embedded system because life cycle of micro processor is shortened. In this paper we study Properties of micro kernel and Comparative Performance of Nucleus and
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정보 가전 분야에 있어서 급속한 기술 발전으로 인해 하루가 다르게 새로운 기능이 추가됨에 따라 임베디드 시스템 소프트웨어의 크기 및 복잡도 또한 함께 증가하고 있고 이를 개발하고 유지보수 하는데 있어서도 막대한 비용과 노력이 요구된다. 이를 해결하기 위한 방안으로 소프트웨어의 재사용성을 높이기 위한 노력이 이어지고 있다. 본 논문에서는 프로세스 방식 기반의 OS를 적용한 소프트웨어를 스레드 방식의 OS 기반의 소프트웨어로 전환하여 임베디드 시스템을 구현하였으며 소프트웨어 방법론으로는 스레드 방식의 OS 기반 소프트웨어에 수정된 DARTS(Design Approach to Real- Time Systems) 방법론을 적용하여 시스템을 구현하였다. 이 구현된 시스템에서 재사용성을 측정하여 표로 제시하며 그 측정 결과를 분석하였다. 그리고 스레드 방식의 OS 기반 소프트웨어에 수정된 DARTS 방법론을 적응하여 코드만 재사용이 아니라 설계방법도 재사용이 가능함을 CE 제품에 보이고자 한다.
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This paper describes an implementation of Home network Control Protocol(HnCP) and it's application to an Intelligent lighting system. The HnCP was announced by korea PLC forum in June 2003 to provide a network protocol for PLC based home appliances. The HnCP master and HnCP slaves were implemented using XPLC30 which is an SOC with ARM9 core. The efficacy of the developed HnCP network modules were shown by applying them to a intelligent lighting system composed of dimmable fluorescent lamps. An extended message set was proposed for the intelligent lighting system and we proposed some directions for the future development of HnCP.
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Recently, many auto makers and OEM are now developing various telematics control units(TCU). TCU has an embedded OS and many user-friendly services inherently and frequently the driver operates the TCU on driving a car. Although the TCU has some accident resistive functions, secondhand accidental problem arose. Current Korean domestic TCUs have some interfaces such as push-button, touch screen, voice recognition and etc. But, because of operational complexity, technical limitation, it has not sufficient user-friendly interface. In this paper, to overcome this problem, haptic devices are considered. We present haptic devices and applications on the basis of that of U.S. Immersion co. and also BMW's iDrive technology.
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In this paper, a simulator system for Fuel Cell Hybrid Electric Vehicles(FCHEV) is implemented using DSP boards with CAN bus. The subsystems of a FCHEV i.e., the fuel cell system, the battery system, the vehicle dynamics with the transmission mechanism are coded into 3 DSP boards. The power distribution control algorithm and battery SOC control are also coded into a DSP board. The real-time monitoring program is also developed to examine the control performance of power control and SOC control algorithms.
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The intelligent PVR(Personal Video Recorder) is an enhanced PVR that provides viewers with some advanced features as well as pause, instant replay, search and skip forward found in conventional PVRs. By embedding a home server into a PVR, it is possible for an intelligent PVR to provide a powerful web-based management user interface constructed using HTML, graphics and other features common to web-browsers. When applied to other embedded systems, web technologies offer graphical user interfaces which are user-friendly, inexpensive, cross-platform and network-ready. It is the purpose of this paper to introduce implementation of intelligent PVR which is control by internet. We present the architecture of an home- server with a simple but powerful web-based network interconnection.
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Because of the demands for high performance and high integrated system, the needs for optimal platform becomes more importance. Optimal platform can handle more data effectively with same resources. AMBA(Advanced Microprocessor Bus Architecture)
$^{TM}$ defines on-chip communication standard for designing high performance embedded micro-controllers. It is consisted of AHB, ASB and APB. It can support fast implementation and reliability in system that is composed with reusable IPs. DMAC is one of master in system and generate master signals of AHB to communicate data from one slave(peripheral or memory) to another slave. It can reduce burden of CPU and increase system performance. We designed DMAC based on AMBA and it supports 13 Channels. Each channel can be controlled by software program. It decides channel's priority using round-robin method. It can support P2P, P2M, M2P and P2P communication. -
The non-ideal characteristics of wireless communication are found in sensor network. And sensor network must also address new raised issues. The efficient ad-hoc routing algorithm is considered the nice solution for new raised sensor network problems. To design this efficient ad-hoc routing algorithm, we study and evaluate new components in routing algorithm. Namely, new components are Link estimator, Neighbor table and Parent selection. We have tested this related experiment using the TIP-30C. TIP-30C is sensor network node that is designed by KETI(Korea Electronic Technology Institute).
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This raper deals with a platform for diagnosis monitoring of partial discharge based on Java virtual machine. This platform is designed for estimating diagnostic parameters of partial discharge signal and displaying Web-page on operating status. For Web-service, hardware of platform is based on a Strongarm processor and software base is designed on Linux and java virtual machine.
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Sensor network supports data delivery from physical world to cyber space Sensors get physical events then wireless network transfers sensor data to service server. We use sensor network technology to manage location information of asset. In ubiquitous computing environment, user localization is basic context for intelligent service. A lot of research group make effort to develop low cost localization technology. In this paper, we propose asset monitoring system using wireless sensor network. It is implemented using ad hoc network technology which can be adopted to smart home and this system can monitor the asset location and movement.
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현재 대부분의 가정에선 아날로그 제품을 찾아보기 힘들 정도로 상당부분 디지털화되어 있다. 이로 인해 홈 서버나 홈 게이트웨이를 이용한 디지털 가전의 제어도 가능해 졌다. 미래 가정의 지능화에 대한 노력 또한 함께 진행되고 있다. 가정 내의 다양한 환경 및 상황 정보를 감지하여 가정환경을 최적화시키는 것이 센서 네트워크를 이용한 기본적인 지능화 애플리케이션이다. 디지털화된 가정환경에 지능적인 요소를 부여하기 위해 센서 네트워크를 구축하려는 다양한 시도가 진행 중이다. 이에 따라, 가정을 지능화하려면 다양한 상황 데이터를 수집하여 이를 중앙 처리장치로 보낼 수 있는 센서 네트워크 모듈과 수집된 상황 데이터를 수집 분석하여 제어 명령을 전달할 수 있는 센서 네트워크 게이트웨이가 필요하다. 또한 기존 홈 네트워크 사용자를 위해 기존 홈 네트워크와도 호환되어야 한다. 따라서 본 논문에서는 센서 네트워크 게이트웨이를 경량화 하여 저가로 구현할 수 있는 시스템을 제안하였다.
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Bluetooth is a promising wireless personal area network technology and is on the verge of being ubiquitously deployed over wide range of devices. This paper aims to implement a wireless network for image transmission using Bluetooth technology. The characteristics of Bluetooth are small size, low band width and low power consumption, However, there are some difficulties in implementing a wireless radio network using Bluetooth since a lot of repeaters may needed when Bluetooth depends a role of host on personal computer for data transmission. In this paper, a method to implement a wireless radio network is proposed and applied for image transmission using a small size microprocessor for each Bluetooth.
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In this paper, we aim to design and implement supporting IPv6 Bluetooth Access point(AP) in Linux. Bluetooth is a cable replacement technology designed for short range ad-hoc connections, which most likely change the way we handle and access information in the near future. In Personal Area Network(PAN) mobile devices need many IP address space, then we need next generation Internet Protocol(IPv6). We designed Bluetooth Access Point with Bluetooth stack and MAC bridge function in Linux. The implementation tested on Linux system based on Bluetooth Access Point with other Bluetooth devices.
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Voltage Scaling for Reduced Energy Consumption in Real-Time Systems Using Variable Voltage ProcessorEnergy consumption has become an increasingly important consideration in designing real-time embedded systems. In this paper, we propose a voltage scaling method to reduce energy consumption in fixed priority real-time systems using variable voltage processors. The Hyperperiod of tasks is divided into dimains. The most suitable voltage of each domain is determined off-line and stored in a table. During task execution, the voltage of processor is adjusted according to the information of the table. A simulation result shows that the proposed method can reduce 80% of power consumption in comparison to no power management. The difference to the optimal EDF based method is only 5%.
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Song, Min-Gyu;Byun, Do-Young;Je, Do-Heung;Kim, Kwang-Dong;Roh, Duk-Gyoo;Oh, Se-Jin;Lee, Bo-Ahn 441
With the rapid development of the Internet over the recent years, in conjunction with the transmission protocol TCP/IP and the latest version of hypertext(HTML) facilities, new opportunities have come into existence for the use of the network for the remote control of experiments and the other practical systems in engineering education. Using graphical software environments in client-server systems, remote control and monitoring system can be easily designed. Client-server systems have some general advantages when compared with simple Remote-Access Systems. In this paper we present a client-server architecture for the distributed measurement system of instrumentation over the Internet. The proposed solution allows multi-user, multi-instruments sessions to be obtained by means of a queuing process and provides instrument lock capability. Client applications can be easily developed by using conventional high-level programming languages or well-assessed virtual instrumentation frameworks. -
We proposed the method of the production of the humanoid biped robot and apply the A* path finding algorithm, for that robot mainly used in game and mobile robot, to avoid obstacles at real time. Actually we made the robot which has 20 DOF, 12 DOF in the two legs, 6 DOF in the two arms and each 1 DOF in the neck and waist, to realize human motions with minimal DOF, And we use the CATIA V5 for 3D modeling design and simulate.
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Every movement, perception and thought we perform is associated with distinct neural activation patterns. Neurons in the brain communicate with each other by sending electrical impulses that produce currents. These currents give rise to electrical fields that can be measured outside the head. It shows some variation on the electroencephalographic signals. In recent devices, the EEG signals measured from head surface are a sum of all the momentary brain activation. With these EEG signals, it is difficult to distinguish the patterns correlated with a certain event from the signals. However, the system must discriminate some patterns with some events especially for any kind of device as a brain control interface system. In this experiment, the sensory-motor cortex of humans has been extensively studied. Activation related to several movements on both sides of the sensory-motor cortices in imaginary. The activation patterns during imagination of several movements resemble the activation patterns during preparation of movements. The result represents the system based on the optimal filters discriminated at least 60% of mental imageries.
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The quality of agricultural products is represented a degree of freshness and a special quality related to a commercial value. To grade cucumber, the charge-coupled device(CCD) camera is only used to measure external qualities like color. size and degree of bended cucumber The processed area of the image replaces the weigh of cucumber. That means there is no longer used the weighing beams. The system consists of Image processing system and distributing system. This paper explains the structure and movement of the automatic grade system and applies the algorithm for deformed cucumber and characteristics of cucumber through image processing to the grade system.
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Recent medical robot systems perform surgery operations, by following the preplanned trajectory and surgical procedures. Depending on the complexity of surgery operations, they are operated in manual, semi-automatic or full automatic mode. To improve the performance of those medical robot systems, development of the simulator and more advanced auto-illumination system, in which intensity of light, direction and focal point can be controlled automatically according to the varied environments during surgical operations. are required. Therefore, in this paper, the simulator for SPINEBOT system which is a computer-intergrated robotic surgery system are developed. And further, an auto-illumination system which will be integrated to the SPINEBOT system is investigated and its preliminary design is described.
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This paper presents an implementation of real-time speaker localization using audio-visual information. Four channels of microphone signals are processed to detect vertical as well as horizontal speaker positions. At first short-time average magnitude difference function(AMDF) signals are used to determine whether the microphone signals are human voices or not. And then the orientation and distance information of the sound sources can be obtained through interaural time difference and interaual level differences. Finally visual information by a camera helps get finer tuning of the speaker orientation. Experimental results of the real-time localization system show that the performance improves to 99.6% compared to the rate of 88.8% when only the audio information is used.
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Song, Min-Gyu;Byun, Do-Young;Je, Do-Heung;Kim, Kwang-Dong;Roh, Duk-Gyoo;Oh, Se-Jin;Lee, Bo-Ahn 462
ActiveX is the general name for a set of Microsoft Technologies that allows users to re-use code and link individual programs together to suit their computing needs. In addition ActiveX technology Provides a standard model for interapplication communication that different programming language. ActiveX is based on COM(Component Object Model), the COM standard allow developer to create code and application from a multitude of different languages and build a defined interface to that code, making it easily accessible by other application. By using ActiveX, user can access the functionality of other applications running remote computer distributed through the network and communicate over the network to build distributed applications. LabVIEW provides access to other Windows applications using ActiveX technologies. So in this paper we implement distributed application using ActiveX technology for remote control and monitoring. -
This paper deals with the design and analysis of automatic virus infection machine, which can be used in blood testing at veterinary hospital. It consists of the mechanical positioning parts and electrical control parts. Two of driving motor and ball screws are used to move the liquid container into the test position and mix the blood on litmus paper. In addition, a thermal controller is installed to keep the container temperature on constant level. The user interface using with a LCD and some keys are supplied with a 8-bit single chip controller. All of the designs issue related with the mechanism and controllers are discussed in detail. Finally the proposed machine is tested in real experiment with the formal processing to judge the virus infection, and also the usefulness of designed algorithm is verified through the experiments.
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현재 세계적인 열차제어의 추세는 궤도회로에 의한 고정폐색방식을 이용한 열차 운행이 아닌 발리스 또는 무선통신에 의한 이동권한을 이용한 열차제어방식을 적용하고 있으며, 국내에서도 이에 맞추어 철도청에서는 ATP 사업을 통하여 발리스에 의한 이동권한을 이용한 열차제어시스템을 적용하고 있다. 또한 분당선에서는 통신기반 열차제어시스템인 CBTC 시스템을 시범구축하고 있다. 이러한 추세에 맞추어 통신기반 열차 제어 시스템을 적용하기 위한 열차제어 알고리즘이 요구되며, 본 논문에서는 이러한 이동권한에 의한 열차제어 알고리즘을 개발하고 이를 시뮬레이션 하였다.
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현재 세계적인 열차제어의 추세는 궤도회로에 의한 고정폐색방식을 이용한 열차 운행이 아닌 발리스 또는 무선통신에 의한 이동권한을 이용한 열차제어방식을 적용하고 있으며, 국내에서도 이에 맞추어 철도청에서는 ATP 사업을 통하여 발리스에 의한 이동권한을 이용한 열차제어시스템을 적용하고 있다. 기존의 궤도회로를 이용한 열차제어시스템에서는 열차를 궤도회로에 의해 검지하였으나 발리스 또는 무선통신에 의한 이동권한을 이용한 열차제어시스템에서는 궤도회로를 사용하지 않기 때문에 이에 패한 새로운 접근이 요구된다. 본 논문에서는 특히 발리스를 이용하였을 때 열차 검지 및 속도 검지를 위한 방안에 대해 연구하였다.
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This paper deals with a design experience of Control Element Drive Mechanism (CEDM) that is used to withdraw or insert control rods in nuclear reactor. The design is carried out to satisfy the performance requirements for CEDM that were given to ensure reliable and secure actions of the rods. The electrical parameters for four coils that energize the mechanical actuators in CEDM are determined first, Then a computer simulation for CEDM with these coils is performed to see how it works. An adjustment of the coil parameters is made from the simulation results. Finally, it is shown that our final design is valid to guarantee the required performance since the FEM(finite Element Method) calculation shows sufficient vertical attraction forces of a lift armature and a latch magnet, and good dynamics with a full load.
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다이아몬드 톱날을 이용한 얇은 Si 웨이퍼의 기계적인 다이싱은 chipping, crack 등의 문제점을 발생시킨다. 또한 stacked die 나 multi-chip등과 같은 3D-WLP(wafer level package)에서 via를 생성하기 위해 현재 사용되는 화학적 etching은 공정속도가 느리고 제어가 힘들며, 공정이 복잡하다는 문제점을 가지고 있다. 이러한 문제점을 해결하기 위해 현재 연구되고 있는 분야가 레이저를 이용한 웨이퍼 다이싱 및 드릴링이다. 본 논문에서는 UV 레이저를 이용한 얇은 Si 웨이퍼 다이싱 및 드릴링 시스템에 대해 소개하고, 웨이퍼 다이싱 및 드릴링 실험결과를 바탕으로 적절한 레이저 및 공정 매개변수에 대해 설명한다.
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Many application in robotics, telecommunication, automation systems etc require powerful actuator. The powerful actuator have Speeds up to high speed and high output torque efficiencies. To accomplish a powerful actuator, these powerful motor have to be combined with gearheads of the same outer diameter. So, we have developed BLDC motor and planetary type gearheads as powerful actuator. The BLDC motor have advantages that compact structure, high efficiency, high reliability. The Planetary type gearheads have advantages that same-axle structure, high torque transmission, low noise in comparison with spur gearheads. In this study included BLDC motor and planetary type gearheads design, manufacture. This time study performed for actuator of precision mechanism.
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In this paper, the power electronics requirement and the controls of an induction motor for fuel cell electric vehicle system are presented. The power topology is selected based on performance, cost, size, volume, manufacturability, component count and simplicity. Another highlight of the topology is the reduction of battery bank and its control strategy. The proposed approach consists a full-bridge DC/DC converter to boost the fuel cell voltage. The induction motor operated with vector control is driven by a three-phase PWM inverter supplied by the DC-link voltage. The investigation of the electric vehicle performed due to parameter variation of the induction motor has been presented.
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As the electrodes are not needed, the electrodeless lamps using the induction discharge have a long lifetime and are robust against the variable output condition of a ballast. This paper proposed a dimmable resonant inverter for the electrodeless lamps. The proposed resonant inverter formed a half bridge inverter adopted FWM to control the average output power of the inverter and the illumination of a lamp. In this paper, the proposed dimming algorithm was described and the prototype experimental setup for 100W electrodeless lamps was carried out to verify the validity of the proposed dimming method.
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This paper presents an obstacle avoidance of a mobile robot by the subgoal generation using infrared sensors. When an obstacle appears on the path which the robot is moving forward the robot has to get information, such as distance between the robot and the obstacle and the shape of the obstacle for avoidance behavior. Our collision avoidance algorithm needs the only distance between the robot and the obstacles. The distances are used for subgoal generation. Simulation results show that a robot can go to the goal, carrying out subgoal generation and avoiding obstacles.
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In this paper, shows a research in accordance with the design the implementation of the localization system for mobile robot using INS(Inertial Navigation System) and GPS(Global Positioning System). First, a Strapdown Inertial Navigation System : SDINS is designed and implemented for low speed walking robot, by modifying Inertial Navigation System which is widely used for rocket, airplane, ship and so on. In addition, thesis proposes the localization of robot with the method of loosely coupled method by using Kalman Filter with INS/GPS integrated system to utilize assumed position and steed data from GPS.
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An action-selection-mechanism is proposed to deal with sequential behaviors, where associations between some of stimulus and behaviors will be learned by a shortest-path-finding-based reinforcement team ins technique. To be specific, we define behavioral motivation as a primitive node for action selection, and then sequentially construct a network with behavioral motivations. The vertical path of the network represents a behavioral sequence. Here, such a tree fur our proposed ASM can be newly generated and/or updated. whenever a new sequential behaviors is learned. To show the validity of our proposed ASM, some experimental results on a "pushing-box-into-a-goal task" of a mobile robot will be illustrated.
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Seo, Kyu-Tae;Kim, Ki-Woo;Sim, Jae-Yang;Oh, Jun-Young;Lim, Sung-Duk;Lee, Bo-Hee;Kong, Jung-Shik;Kim, Jin-Geol 499
This paper deals with the implementation of a quadruped working robot using wireless sensor network with TinyOS. It is often required to install real time OS and wireless network in the mobile robot field since robots work alone without human intervention and also exchanging their information between robot systems. The suggested controller utilizes a built-in wireless network OS and makes the variance action related with human-kindly motions for a quadruped walking robot. In addition, a kinematics analysis of its structure and control architecture of robot system is suggested and verified the usefulness through the real experiment. -
With rapidly growing of computer and internet technology, Internet-based tote-operation of robotic systems has created new opportunities in resource sharing, long-distance learning, and remote experimentation. In this paper, remote control system of a mobile robot through the internet has been designed. The internet users can access and command a mobile robot in the real time, receiving the robot's sensor data. The overall system has been tested and its usefulness shown through the experimental results.
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This paper presents a measurement of ZMP using FSR sensors, and then the ZMP control with measured ZMP on single leg. ZMP is mostly used as standard evaluation of stability of a humanoid robot. The ISHURO has 5 sensors which are mounted at each corner and center of a sole. ZMP is computed using a model of a humanoid robot and information from the joint encoders. And we may able to use measurement data from FSR sensors at the robot feet. IP(Integration Proportional) control algorithm is applied to position control of ZMP that is an error of desired ZMP between measured ZMP.
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In this paper, we proposed the GPS position data correction method for autonomous land navigation using vanishing point property and a monocular vision system. Simulations are carried out over driving distances of approximately 60 km on the basis of realistic road data. In straight road, the proposed method reduces GPS position error to minimum more than 63% and positioning errors within less than 0.5m are observed. However, the average accuracy of the method is not presented. because it is difficult to estimate it in curve road or other road environments.
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Camera Calibration should certain)y be achieved to take an accurate measurement using image system. Calibration is to prove the relation between an measurement object and camera and to estimate twelve internal and external parameters. In this paper, we suggest that an algorithm should estimate the external parameters from the road image and use a vanishing point's character from parallel straight lines in a space. also, we use Hough Transform to estimate an accurate vanishing point. Hough Transform has one of the advantages which is an application for each road environment. we assume a variety of environments to prove the usability of a suggested algorithm and show simulation results with a computer.
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국내 및 국외에서 많은 시뮬레이션 환경이 개발되어 다양한 시뮬레이터 개발에 활용되고 있다. 이러한 시뮬레이션 환경은 다양한 기능을 갖추고 있어 시뮬레이터 개발편의를 도모하고 있다. 이러한 시뮬레이션 환경에서는 시뮬레이션 스케줄링(Scheduling), 데이터베이스(Database), 모델 컴파일 그리고 디버거(모니터링 및 제어기능 툴)등을 제공한다. 이미 국내 및 국외 업체에서 시뮬레이션 환경이 개발되어 왔지만, 3차원적인 시뮬레이션을 필요로 하는 시뮬레이션 환경은 미비한 상태로 로봇공학이나 3차원 시뮬레이션이 필요한 산업에 앞으로 더욱더 개발이 필요한 실점이다. 본 논문에서는 3차원 시뮬레이션을 하기 위한 방안으로 개발된 3D 모델빌더와 시뮬레이션 환경인 3DSIM(3D Simulation Environment)을 소개한다. 3DSIM은 현재 사용되고 있는 시뮬레이션 환경과는 다른 형식의 구조를 갖추고 있어 일반 시뮬레이션 환경과의 차이점에 대해 알아본다. 일반적인 시뮬레이션 환경은 서버와 클라이언트로 나뉘어 서버에서는 특정 모델에 대한 연산을 수행하기 위한 환경을 제공하며, 클라이언트에서는 서버에서 수행된 연산을 효율적으로 분석하기 쉽도록 보여주는 환경으로 나된다. 하지만, 3차원 시뮬레이션 환경인 3DSIM은 3차원 객체를 디자인하는 과정이 필요하며, 3차원 객체를 디자인하였을 경우, 각각의 파라미터를 통하여 시뮬레이션 되어야 한다는 점에서 일반적인 시뮬레이션 환경과의 구조가 다르게 된다. 3DSIM개발을 통하여 3차원 시뮬레이터 개발을 보다 편하게 개발할 수 있도록 하였으며, 시뮬레이션 모니터링 및 제어가 용이하도록 개발하였다.
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This paper describes an approach to estimate a robot pose with an image. The algorithm of pose estimation with an image can be broken down into three stages : extracting scale-invariant features, matching these features and calculating affine invariant. In the first step, the robot mounted mono camera captures environment image. Then feature extraction is executed in a captured image. These extracted features are recorded in a database. In the matching stage, a Random Sample Consensus(RANSAC) method is employed to match these features. After matching these features, the robot pose is estimated with positions of features by calculating affine invariant. This algorithm is implemented and demonstrated by Matlab program.
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In this paper, we propose the algorithm of path planning and obstacle avoidance for mobile robot. We call the proposed method Random Access Sequence(RAS) method. In the proposed method, a small region is set first and numbers are assigned to its neighbors, then the path is selected using these numbers. It has an advantage of fast planning and simple operation. This means that new path selection may be possible within short time and that helps a robot to avoid obstacle in any direction. When a robot meets moving obstacles, it avoids obstacles in a random direction. Sonar ranger is useful to get obstacle information and RAS may be a good solution for path planning.
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Over the last few years, the control of bipedal robot has been considered a promising research field in the community of robotics. But the problems we encounter make the control of a bipedal robot a hard task. The complicated link connection of the bipedal robot makes it impossible to achieve its exact model. In addition, the joint velocity is needed to accomplish good control performance. In this paper a control method using ANFIS as an system approximator is purposed. First a model biped robot of a biped robot with switching leg influence is presented. Unlike classical method, ANFIS approximation error estimator is inserted in the system for tuning the ANFIS. In the entire system, only ANFIS is used to approximate the uncertain system. ANFIS tuning rule is given combining the observation error, control error and ANFIS approximation error. But this needs velocity information which is not available. So a practical method is newly presented. Finally, computer simulation results is presented to show this control method has good position tracking performance and robustness without need for leg switching acknowledgement.
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This paper focuses on planning strategies for object interception, especially with minimum time. Herein, the goal is for robot to intercept object with minimum time on a conveyor line that flows to x-axis with respect to world coordinate system. In order to do it, conveyor system needs the algorithms for minimizing time. This objective is achieved by solving about two problems: selection of a minimum-time interception point and planning of an optimal robot trajectory. Herein, the first problem is formulated a minimization of the robot-object interception time.
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For localization, it is very important for an autonomous mobile robot to be able to recognize indoor environment and match an object it detect to an object within a map developed either online or offline. Given the map defining the locations of geometric beacons like wall and comer existing in the robot operation environment, this paper presents a stereo ultrasonic sensor based method that can be conveniently used in recognizing the geometric beacons. The stereo ultrasonic sensor used in the experiment consists of an ultrasonic transmitter and two ultrasonic receivers placed symmetrically about the transmitter. Experiment shows that the proposed method is more efficient in recognizing wall and coner than the conventional method of using multiple number of transmitter-receiver pairs.
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The advancement of electronics and telecommunication technologies has forced the risk management system for underground metallic structures to evolve into the remote monitoring and control system. Especially, facilities such as gas pipelines, oil pipelines and water distribution lines might make hazardous effect on human safety without continuous monitoring and control. As a result, pipeline engineers have applied cathodic protection system to prevent the degradation of their facilities by corrosion and carried out a periodic monitoring of the pipe-to-soil (P/S) potentials at numberous test boxes along their pipelines. The latter action on a road in downtowns, however, is so much dangerous that the inspectors should be ready to suffer the threatening of their lives and maintenance. In order to minimize these social costs and hazards, a stand-alone type corrosion monitoring equipment which can be installed in test box, store the P/S data for given Belied and send the data by wired/wireless telecommunications is under development. In order to obtain the exact P/S data, however, a reference electrode should be located as close to the pipeline as possible. Actually, the measured potential by a conventional portable reference electrode contain inevitably an IR drop portion caused by the current flow from the cathodic protection rectifier or the subway railroad. To minimize this error, it is recommended that the reference electrode should be buried within 10 cm from the pipeline. In this paper, we describe the design parameters for fabricating the permanent type reference electrode and the characteristics of the developed reference electrode.
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The flame image processing and it's analysis system has been developed for optimal coal firing of thermal power plant, especially for reducing NOx and safe operations. We aimed at gaining the relationship between burner flame image, emissions of NOx and LOI(Loss on ignition) in furnace by utilizing the flame image processing methods. And the relationship determines quantitatively the conditions of combustion on the individual burners. The test was conducted on Samchonpo thermal power plant #4 unit(560MW) of KOSEP which has 24 burners. The system simplified the burner adjustment works in accordance with the real time trending of flame behavior like NOx profiles and unburned carbon profiles for individual burners. But, This kind of conventional method increases the cost as the number of burner are increased. Also there is a difficulty to measure exhausted gas of each burner because of measurement errors. This paper intends to propose the useful "Flame Monitoring System" that can find Low NOX and LOI at the upper furnace and to compare with the conventional System.
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Electrical currents generated by human heart activities create magnetic fields represented by MCG(MagnetoCardioGram). Since an MCG signal acquisition system requires precise and stable operation, the system adopts hundreds of SQUID(Superconducting QUantum Interface Device) sensors for signal acquisition. Such a system requires fast real-time data acquisition in a required sampling interval, i.e., 1 mili-second for each sensor. This paper presents designed hardware to acquire data from 256-channel analog signal with 1 ksamples/sec speed, using 12-bit 8-channel ADC devices, SPI interfaces, parallel interfaces, 8-bit microprocessors, and a DSP processor. We implemented SPI interface between ADCs and a microprocessor, parallel interfaces between microprocessors. Our result concludes that the data collection can be done in
$168{\mu}sec$ time-interval for 256 SQUID sensors, which can be interpreted to 6 ksamples/sec speed. -
An optimal soot blowing system has been developed for an optimal operation of power utility boilers by both minimization of the use of steam and the number of soot blowers worked during soot blowing. Traditionally, the soot blowing system has been operated manually by operators. However, it causes the reduction of power and thermal performance degradation because all soot blowers installed in the plant should be worked simultaneously even there are lots of tubes those are not contaminated by slagging or fouling. Heat transfer area is divided into four groups, furnace, convection area including superheater, reheater and economizer, and air preheater in the present study. The condition of cleanness of the tubes is calculated by several parameters obtained by sensors. Then, a part of soot blowers works automatically where boiler tubes are contaminated. This system has been applied in a practical power plant. Therefore, comparison has been done between this system and manual operation and the results are discussed.
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This paper designs and evaluates a complementary filter for fusion of inertial sensor signals. Specifically, the designed filter is applied to inverted pendulum control where the pendulum's angle information is obtained from low-cost tilt and gyroscope sensors instead of an optical encoder. The complementary filter under consideration is a conventional one which consists of low- and high-pass filters. However, to improve the performance of the filter on the gyroscope, we use an integrator in the filter's outer loop. Frequency responses are obtained with both tilt and gyroscope sensors. Based on the frequency response results, we determine appropriate parameter values for the filter. The performance of the designed complementary filter is evaluated by applying the filter to inverted pendulum control. Experiments show that the performance of the designed filter is comparable to that of an optical encoder and low-cost inertial sensors can be used for inverted pendulum control with the heir of sensor fusion.
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This system is monitors the degree of aging happened at the electric machine. It detects electromagnetic wave generated from the insulator when the voltage is applied to the machine. By analyzing the internal and external factors make the electric, mechanic, or thermal characteristics of the electric machinery deteriorate the electric insulation and eventually cause the partial electric discharge. The continuous partial electric charge accelerates the insulation aging and the insulation breakdown happens at last. This system consists of the relays connected with 10 sensors (40 total) detecting the partial electric discharge ans the temperature, the server, ans the program analyzing and storing the data.
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In this paper, access protocol is proposed that can optimally control the radio buoy system used for inshore and deep sea fishery. Proposed protocol can minimize the power consumption of radio buoy and can ensure high security from burglary and loss, and it enable a mother ship to control remotely more than 150 radio buoys simultaneously. GPS technology and remote control techniques are used to monitor the exact location and status of the radio buoy system in real time.
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In this paper, high performance radio buoy system used for inshore and deep sea fishery is developed and experimented. Location of radio buoy can be accurately monitored and traced by the mother ship using GPS technology, and optimum access protocol is adopted to minimize the power consumption of radio buoy system. Developed system can cover over 80Km coastal range with 8 W transmitting power and -115 dBm receiver sensitivity and can ensure high security from burglary and loss using digital coding technology.
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In this paper, we introduce a new method of detecting faults for a power converter unit in Control Rod Control System. The faults of a power converter unit can exert harmful influence upon the operation of Control Rod Drive Mechanisms and the control of the reactor output. This situation makes the quick and correct detection of failures in a power converter unit very important. We devise a new method of fault detection for the digital power controller and improve the drawbacks of the existing fault detector.
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In this paper, we design two types of Main Control Unit for Control Rod Control System and Control Element Drive Mechanism Control System, respectively, using a domestic Distributed Control System(DCS) developed to localize the instrumentation and control(I&C) system for nuclear power plant(NPP). There are many parts developed by domestic skills and being operated successfully in NPP, but the development of I&C system as an essential part has been slow in progress. We will show the great possibility of developing peculiar Korean I&C system by applying this domestic DCS to nuclear I&C system and confirming its successful operation.
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The containment leakage rate test performed on the nuclear power plants consists of following phases : pressurizing the containment, stabilizing the atmosphere, conducting a Type A test, conducting a verification test, depressurizing the containment. It takes more than 48 hours from the pressurization to the depressurization and the prediction of the results will help to prepare the next test phase. In this paper, to predict the leakage rate, the prediction methods based on the least square method are evaluated according to the input variables and the measurement period.
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In active noise control (ANC) systems, the convergence behavior of the conventional Filtered-X Least Mean Square (FXLMS) algorithm may be affected by nonlinear distortions in the secondary path (e.g., in the power amplifiers, loudspeakers, transducers, etc.), which may lead to degradation of the error-reduction performance of the ANC systems. In this paper, a stable FXLMS algorithm with fast convergence is proposed to compensate for undesirable nonlinear distortions in the secondary-path of ANC systems by employing the Volterra filtering approach. In particular, the proposed approach is based on the utilization of the conventional P-th order inverse approach to nonlinearity compensation in the secondary path of ANC systems. Finally, the simulation results showed that the proposed approach yields a better convergence behavior In the nonlinear ANC systems than the conventional FXLMS.
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This paper presents a study of a position finding system using PSD Sensor and Pan/Tilt. The position of PSD(Position Sensitive Detector) sensor is calculated by the degree of pan-tilt and the difference in height between pan-tilt and PSD. For that, the DSP which control pan-tilt is used for precise operation. The PIC microcontroller process PSD sensor data that indicate light incident position. A user using computer can acquire the conditions of pan-tilt and PSD and issue an order.
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본 논문에서는 휴대용 선량계 시스템에 거리 무선 통신 방식중 Bluetooth를 이용하여 선량계를 구현한 것에 대해 논하였다. 휴대용 선량계란 감마선과 속중성자 및 열중성자를 현장에서 실시간으로 측정 할 수 있는 기기이다. 휴대용 선량계는 선랑계의 소형화를 위해 모듈별로 구성하여 공간의 최적화를 취하였다. 모듈의 구성은 시스템의 전반적인 제어를 하는 CPU부 센서로부터 측정한 데이터를 처리하는 신호처리부 방사선량을 측정하는 센서부로 구성되어졌다. 센서 모들의 PIN 다이오드와 MODFET 센서를 이용하여 감마선, 속중성자, 열중성자를 측정한다. 휴대용 선량계를 관리하고 측정한 데이터의 백업 및 분석을 위하여 PC용 관리프로그램과 근거리 무선 통신(Bluetooth)을 사용하여 통신하도록 만들어 사용하였다. 측정 지역의 방사선량을 휴대용 선량계로 측정하여 PC용 관리프로그램에서 실시간으로 방사선량을 확인 할 수 있다.
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The directivity of the sound pressure increases the sensitivity of the incoming sound from specific directions. The directivity measurement of the sound pressure is usually done in an anechoic room using a sloping motor. In this paper a replaceable anechoic chamber was designed for the acoustic directivity pattern measurement. Electrical equipments were interfaced with a PC for experiment automatic control. Some comparative results are shown in the result.
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Digital hearing aids enclose
$6{\sim}8$ tiny components. Those electromechanical components are individually wired by soldering which is a manual labor and sometimes causes components' damage by heating. This paper suggests a PCB design for overcome these problems. Several PCBs are designed and manufactured and circuited to produce ITE(In The Ear) type hearing aids which are inserted in the ear canal. The most optimal size of the PCB design for the ITE hearing aid is presented in this paper. -
As the demand of large and high-resolution display panels is increased, the black light units (BLU) of the display devices play an important roles. In this study we'll deal with various defects of BLUs. Patterns of defects can be classified by the scratches, the non-uniform misprinting for the diffused reflection, the surface stains, spots and etc. Due to these distorted patterns the high-resolution and high-precision could be impeded. We'll propose the visual inspection system to detect various defects by pattern-matching.
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In this paper we will deal with a calibration method for low cost motion capture system using psd(position sensitive detection) optical sensor. To measure the incident direction of the light from LED emitted marker, the PSD is used the output current ratio on the electrode of PSD is proportional with the incident position of the light focused by lens. In order to defect the direction of the light, the current output is converted into digital voltage value by opamp circuits peak detector and AD converter with the digital value the incident position is measured. Unfortunately, due to the non-linearly problem of the circuit poor position accuracy is shown. To overcome such problems, we compensated the non-linearly by using least-square fitting method. After compensated the non-linearly in the circuit, the system showed more enhanced position accuracy.
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Although stable control algorithm has been implemented to the biped robot, the stability is not guaranteed because of encoder errors and/or rigid body elastics. Hence precise body pose estimation is required for more natural and long term walk. Specially pelvis sloping by gravity or uneven ground on landing place are most critical reason for undulated motion. In order to overcome these difficulties an estimation system for foot position and orientation using PSD sensors and Gyro sensors is proposed along with calibration algorithm and experimental verification.
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In this paper, we developed a laser distance measurement(LDM) system based on DSP. We applied PPD(Pulsed Phase Detection) algorithm to the LDM system. The PPD algorithm calculate the distance from the LDM system to the object by using phase detection. Reference waveform at a fixed frequency is sampled by both the inner-loop and outer-loop pulse signal. The LDM system detects the difference of phase between the sampled signals. We obtained an accuracy of
${\sigma}=25.5mm$ from the LDM system. -
Camera calibration is an important problem to determine the relationship between 3D real world and 2D camera image. The existing calibration methods can be classified into linear and non-linear models. The linear methods are simple and robust against noise, but the accuracy expectation is generally poor. In comparison, if the non-linearity, which is due mainly to lens distortion, is corrected, the accuracy can be better. However, as the optical features of lens are diverse, no non-linear method can be always effective for diverse vision systems. In this paper, we propose a new approach to correct the calibration error of a linear method using GMDH algorithm. The proposed technique is simple in concept and showed improved accuracy in various cases.
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In this paper range measurement systems using ultrasonic and visual sensors are designed. By varying the focus of a camera, the range to a target pattern is computed. Pour different methods are tested for the focusing-based range measurement. The best result is obtained when counting edge pixels found by Laplacian operator. Higher accuracy can be obtained by fusing the measurement of camera focusing with that of ultrasonic sensor. The system designed is experimented within the range of 300-450mm.
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In this paper, we suggest method that change odors to digital data. For this, we selected emotional adjective of odors as olfactory receptor This emotional adjective(expressional receptor) is about 40. Each odors are expressed by adjective equivalent to oneself. Expressed odors as emotional receptor is encoded as proposed method for transmission, and after transmission, It should be decoded for expression again. The applied decoding method is fuzzy c-means clustering algorithm(FCMA). But, because odor data is expressed to 40 dimensions, FCMA uses a lot of computing times and memories. To solve this problem, after we reduce dimension through principal component analysis(PCA), we use FCMA algorithm.
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A portable electronic tongue(E-Tongue) system using an array of ion-selective electrode(ISE) and personal digital assistants(PDA) for recognizing and analyzing food and drink have been designed. By the employment of PDA, the complex algorithm such as fuzzy c-means algorithm(FCMA) could be used in E-Tongue, FCMA could iteratively solve the cluster centers of pre-determined standard patterns. And the membership between the standard patterns and unknown pattern could be analyzed easily by the present E-Tongue combined with PDA.
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A class D digital audio amplifier with small size, low cost, and high quality is positively necessary in the multimedia era made of home theater system and the digital audio broadcasting (DAB). It is impossible to analyze the stability of the digital audio amplifier, which is based on the PWM signal processing. To solve this problem, the digital audio amplifier is analyzed using variable structure control theory which is one of nonlinear system theories. Moreover, the magnitude and the frequency of ripple signal, which generated by hysteresis in the comparator, is obtained using describing function which is useful to represent the input-output relation of nonlinear system.
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In continuous annealing line (CAL), POSCO, the center position control (CPC) is an essential technique that renders the steel-strip to pass at the center of a roll in order to prevent the strip from skewing or breaking. The CPC algorithm currently installed on the steering roll in the heating section of CAL is to control the strip position by using the reverse phase of error from the center position, without considering the dynamics of strip horizontal movement. Such algorithm may, unfortunately, require a manual operation occasionally when the range of strip input becomes wide, causing the dynamics 0 be dominant. Other PID-type control is rarely used in automatic operation because the excess of response may occur when the discontinuous points such as welding joints pass through rolls. In this paper, we identify the CPC system by using off-line data and design a compensator for the excessive dynamics by using the adaptive inverse control. Simulation result depicts the improved reliability of the proposed CPC system.
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This paper is concerned with the simulation and determination of the input voltage and frequency for the optimal efficiency operation of induction motors. In general, induction motors have a specific character that operation efficiency is dropped sharply at the light roads condition. Consequently, if the induction motor is controlled by high efficiency using the VVVF(variable voltage variable frequency) control methods at optimal values, the entire system can obtain the substantial energy savings from the efficiency improvement in induction motors. In this paper, optimal slip is derived from the modeling of an induction motor and the optimal hybrid-control method is suggested by the simulation of the proposed algorithm for a 3-phase induction motor.
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It is waste of time in industrial plant that the PI controller gain tuning. The PI controller has many trial-and-error steps for gain design. This paper proposes the optimum gain design of PI controller using a speed estimation in sensorless vector-control. In this method, a degree of stability and Hurwitz theory are applied and the controller gain is expressed by system parameters.
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Design Error Corrector of Binary Data in Holographic Digital Data Storage System Using SubclusteringData storage related with writing and retrieving requires high storage capacity, fast transfer rate and less access time in. Today any data storage system can not satisfy these conditions, but holographic data storage system can perform faster data transfer rate because it is a page oriented memory system using volume hologram in writing and retrieving data. System architecture without mechanical actuating part is possible, so fast data transfer rate and high storage capacity about
$1Tb/cm^3$ can be realized. In this paper, to correct errors of binary data stored in holographic digital data storage system, find cluster centers using subtractive clustering and reduce intensities of pixels around centers, so the intensify profile of data rare will be uniform and the better data storage system can be realized. -
Mobility of an indoor wheeled robot is affected by adhesion force that is related to various floor conditions. When the adhesion force between driving wheels and the floor decreases suddenly, the robot has a slip state. In order to overcome this slip problem, optimal slip velocity must be decided for stable movement of wheeled robot. First of all, this paper shows that conventional PI control can not be applied to a wheeled robot of the light weigh. Secondly, reposed fuzzy logic applied by the Takagi-Sugeno model for the configuration of fuzzy sets. For the design of Takaki-Sugeno model and fuzzy rule, proposed algorithm uses FCM(Fuzzy c-mean clustering method) algorithm. In additionally, this algorithm controls recovered driving torque for the restrain the re-slip. The proposed fuzzy logic controller(FLC) is pretty useful with prevention of the slip phenomena through that compare fuzzy with PI control for the controller performance in the re-adhesion control strategy. These procedures are implemented using a Pioneer 2-DXE wheeled robot parameter.
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In Electro-Luminescence Display making process, it is necessary to do high molecule patterning effectively. Recently, one of the most effective way is the patterning method using Ink-Jet head controller. To maximize the effect, it is needed to control each channel of Ink-Jet head and develop that controller. Thus, we implement the Ink-Jet Head Controller which can control the parameters of 128 fire pulses independently, improve the accuracy of patterns more than 100 times previous ones, and apply random patterns.
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This paper describes an 8-bit CMOS folding A/D converter for set-top box. Modular low-power, high-speed CMOS A/D converter for embedded systems aims at design techniques for low-power, high-speed A/D converter processed by the standard CMOS technology. The time-interleaved A/D converter or flash A/D converter are not suitable for the low-power applications. The two-step or multi-step flash A/D converters need a high-speed SHA, which represents a tough task in high-speed analog circuit design. On the other hand, the folding A/D converter is suitable for the low-power, high-speed applications(Embedded system). The simulation results illustrate a conversion rate of 40MSamples/s and a Power dissipation of 80mW(only analog block) at 2.5V supply voltage.
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The proposed output buffer is presented for driving large-size LCD panels. This output buffer is designed by adding some simple circuitry to the conventional two-stage operational amplifier. The proposed circuit is simulated in a high-voltage 0.35um CMOS process with HSPICE. The simulated result is more improved settling time than that of conventional one.
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First for high-qualify images and reducing process-error and driving speed, the designed 8-bit data driving circuit consists of a constant transconductance bias circuit, D-F/Fs by shift registers using static transmission gates, 1st latch and 2nd latch by tristate inverters, level shifters, current steering segmented D/A converters by 4MSB thermometer decoder and 4LSB weighted type. Second, we designed gray amp for power saving. These data driving circuits are designed with
$0.35-{\mu}m$ CMOS technologies at 3.3 V and 18 V power supplies and simulated with HSPICE. -
The containment of the nuclear power plant is the last barrier of radiation release when the reactor coolant pipe rupture is occurred. Each plant has to be tested every 5 years whether the containment leak rate meets its technical specifications. We have developed the leak rate test system and in this paper, we describe the results of the uncertainty analysis on the measurement channels and its propagation to the calculation results.
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The gas stripper system of a nuclear power plant provides gas-free water to a reactor and a turbine system. The gas tripper unit has two control systems to regulate pressure and level independently. Because the level and the pressure interact as a control disturbance each other, continuous operation of the system is difficult. In this paper, We describe the controllability evaluation of the gas stripper system and the results of the optimally tuned control gains.
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Liquid Zone Control System controls the power of heavy water reactor. Changing the level of each zone compartment regulates one local zone power of 14 zone powers, iud the level is limited less than 90% by the control algorithm to prevent the flood. In recent years, the level and the power was controlled oscillatory in the upper zones. To find out the condition of cycling, the zone control system was modelled with the linear difference equations and identified using parameter estimation. The pole-zero plot showed that the major pole was near the stability boundary, and the system had oscillatory characteristics in nature.
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The closed loop identification(CLID) is a very useful method for on-line applications since it can identify the plant in the closed-loop system composed of the plant and the controller. There are some literatures on CLID, but they and mainly focused on SISO(Single-Input/Single-Output) problem. In this paper, a CLID method is proposed for MIMO(Multi-Input/Multi-Output) systems. The CLID method is applied to a MIMO benchmark plant, TRMS(Twin-Rotor MIMO System). To illustrate the performance of the closed-loop system identification., unit step responses in the TRMS are represented and compared with the open-loop identification via some simulation.
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When a controller is implemented by a one-chip processor with fixed-point operations, the finite alphabet problem usually occurs since parameters and signals should be taken in a finite set of values. This paper formulates PID finite alphabet PID control problem which combines the PID controller with the finite alphabet problem. We will propose a PID parameter tuning method based on an optimization algorithm under the finite alphabet condition. The PID parameters can be represented by a fixed-point representation, and then the problem is formulated as an optimization with constraints that parameters are taken in the finite set. Some simulation are to be performed to exemplify the performance of the PID parameter tuning method proposed in this paper.
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본 논문에서는 간접 벡터 제어 방식의 유도전동기를 위한 하이브리드 퍼지 속도제어기를 설계한다. 제안한 하이브리드 퍼지 속도제어기는 유도 전동기의 속도 응답 성능을 향상시키기 위하여 응답 상태에 따라 PI(비계적분) 제어기와 퍼지 제어기를 선택하여 사용하는 형태이다. 정상상태에서는 PI 제어기를 사용하고 속도 오차값이 크면 퍼지 제어기를 사용한다. 또한 사용된 퍼지 제어기는 퍼지 입력의 파라미터를 튜닝하여 응답 성능을 높였다. 본 논문에서 제안한 하이브리드 퍼지속도 제어기와 기존의 PI 제어기의 성능을 실험을 통하여 비교 검증한다.
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This paper outlines the three main fieldbus type standards: Foundation Fieldbus; WorldFIP; and the Profibus, each of which have great advantages over traditional instrumentation networking technology. The paper shows, using their specification, how they improve traditional control and data acquisition methods. By analysing the main robust, how the can be used to distribute data around the control system, provided increased diagnostic information, are easy to implement, fault confinement, and move simple control operations from the main controller to the local environment. This will help to segment industrial plants into zones which can control themselves. The main control will then be responsibility high-level control. and interzone communications.
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CAN is a serial communication bus for real-time controls and automations in distributed control systems. In distributed control systems, occasionally a sensor module and a controller are not in the same node and physically separated. In order for the signal from a sensor node to reach the controller node, the signal must travel through network. CAN has a certain capabilities to deal with real-time data. However, when many nodes on the networks try to send data on the same network, the arbitration mechanism to solve the data collision problem is necessary. This situation causes the time delay which has detrimental effects on the performance of the control systems. This paper proposes a method to solve the problem due to the time delay in distributed control system using CAN. Time delay is approximated to an element with a rational transfer function using Pade approximation and Mu~synthesis method is applied. Since time delay in the network is not constant, the time delay element is considered to be an uncertainty block with a bound. The proposed method is applied to the experimental system with CAN and proved to be effective.
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Park, Jin-Su;Choi, Sung-Dae;Kim, Sang-Hoon;Yoon, Kwang-Ho;Ban, Gi-Jong;Nam, Moon-Hyon;Kim, Lark-Kyo 660
This paper proposes an Intelligent Speed Estimator in order to realize the speed-sensorless vector control of an induction motor. Intelligent Speed Estimator used Model Reference Adaptive System which has Fuzzy-Neural adaptive mechanism as Speed Estimation method. The Intelligent Speed Estimator estimates the speed of an induction motor with a rotor flux of a reference model and adjustable model in MRAS. The Intelligent Speed Estimator reduces the error of the rotor flux between the voltage flux model and the current flux model using the error and the change of error as input of the Estimator. The computer simulation is executed to verify the propriety and the effectiveness of the proposed speed estimator. -
Ethernet-based passive optical network(EPON) technology is being considered as a promising solution for next-generation broadband access network. It must have the property of high efficiency, low cost, and support quality of service(QoS). A major feature for this new architecture is the use of a shared transmission media between all connected optical network unit(ONU). Hence, medium access control(MAC) arbitration mechanisms are essential for the successful implementation of EPON. In this paper we propose a simple dynamic bandwidth allocation(DBA) algorithm that improves the performance of network and supports IP-based multimedia applications with the bursty data traffic. In addition, we introduce analytic models of proposed algorithms and prove the system based on our algorithm to be asymptotically stable. Simulation results show the new DBA algorithm provides high bandwidth efficiency and low queueing delay of ONU in EPON.
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본 논문에서는 RF를 이용한 다용도 디지털 데이터 통신 모듈의 설계와 제작에 관하여 논하였다. RF통신에 대한 기본적인 이론과 적용범위 등을 살펴보았고, 신뢰성 있는 통신을 위해 나름의 프로토콜을 적용하였다. 통신거리 개선을 위해 전력증폭기 시뮬레이션, 안테나 임피던스 매칭에 관한 연구를 해 보았다.
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This paper presents a MIMO nonlinear controller for the power system consisting of a turbine and a synchronous generator connected to an infinite bus. The controller proposed is based on feedback input-output linearization; its main goal is to regulate the terminal voltage and frequency, and is to improve the transient stability under large disturbances and unexpected faults. It is guaranteed that the voltage converges to its reference value exponentially, and that the frequency and the mechanical/electrical power are bounded. The design procedure is tested on a single machine infinite bus power system through simulations, and is seen to be effective.
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Many nonlinear controllers for the power system are based on nonlinear models involving the power angle as an element of the state, and therefore the reference value for the power angle is needed. As this reference value is not generally available, it is difficult to apply such nonlinear control methods in practice. To deal with this problem, we present an input-output feedback linearizing control scheme by selecting the output as a combination of the squared voltage and the relative frequency. It is shown that the internal dynamics are locally stable with controllable damping, and that the frequency remains bounded for all time. Simulations illustrate the effectiveness of the proposed method.
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This paper presents a nonlinear controller design for optical disk drive systems to improve anti-shock performance. The nonlinear anti-shock controller is added parallel to the original linear servo control loop. In the previous work, dead-zone nonlinear element is used for nonlinear controller and PID control method is used for linear controller. Although this strategy improves anti-shock performance, it has a narrow stability bound. In this paper, we propose dead-zone with saturation nonlinear element for the nonlinear controller. Since this nonlinear element improves stability margin, we can use higher gain of dead-zone than the controller with dead-zone only. In the linear controller design, we show that lead-lag control has improved stability margin over PID control. Numerical simulation results show that the proposed method can get better performance to the external shock than previously proposed method.
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In many cases the systems are so complex that it is not possible to obtain reasonable models using physical laws. Also a model based on physical laws contains a number of unknown parameters even if the structure is derived from physical laws. These problems can be solved by system identification. In this paper, plate activity vibration is selected as an example for system identification. The transfer functions of this system is derived by using ARMAX based on input/output data through experiment.
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This paper describes the control of a geared DC motor having a backlash for implementation of a humanoid robot using disturbance observer. Critical problem of the humanoid robot is caused by the nonlinearity such as a backlash. To meet this problem, a control method using disturbance observer has been proposed. The disturbance observer is designed to estimate the effects of nonlinearities in the system, to make the nonlinear system behave linearly. To design the low-pass filter in the disturbance observer, cut-off frequency of the output should be found. The goal of this paper is the implementation of the proposed system, compensating the backlash effect. To accomplish the goat, PD control and disturbance observer are employed to the system with no load and full load. As a result, system stability can be guaranteed by compensating the effect of backlash. In addition, real experiment shows the proposed control methodology will satisfy the stable working of a humanoid type in the future.
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This paper is concerned with the DC motor speed control using distributed control system. We design CAN nodes which can transmit control and monitoring data through CAN bus and apply these to distributed networked control system. The results of the experiment validate effectiveness of our distributed networked control system.
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As using of network increases rapidly, performance of system has been deteriorating because of the overhead and bottleneck. Nowadays, High speed I/O network standard, that is a sort of PCI Express, HyperTransport, InfiniBand, and so on, has come out to improve the limites of traditional I/O bus. The InfiniBand Architecture(IBA) provides some protocols to service the applications such as SDP, SRP and IPoIB. In our paper, We explain the architecture of IPoIB (IP over InfiniBand) and its features in channel based I/O network. And so we provide a performance evaluation result of IPoIB which is compared with current network protocol. Our experimental results also show that IPoIB is batter than TCP/IP protocol. For this test, We use the dual processor server systems and Linux Redhat 9.0 operating system.
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Differently from an existing analog control, because the digital control includes microprocessor basically, the digital control is enable to monitor internal parameters of DC-DC converter and to control output voltage remotely by communicating with a Windows based PC and also to monitor whether exact voltage is output or not. These things are impossible in an analog control. In this paper, a simple flyback converter is taken as a control target and is controlled by a microcontroller(TMS320F2812). This converter can make variable outputs 1.8V to 5V from 30V input voltage remotely in PC. Finally the response characteristics of a step reference voltage and in a steady state are experimented to verify the feasibility and the usefulness of this digital controlled converter.
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Yoon, Kwang-Ho;Kim, Sang-Hoon;Ban, Gi-Jong;Choi, Sung-Dae;Park, Jin-Su;Kim, Lark-Kyo;Nam, Moon-Hyon 693
Among modem control method, the observer is being used widely because it has the advantage of the guarantee of reliability on financial problem, over heating, and physical shock. However, an existing state observer and a sliding observer have such problems that an experimenter needs to know dynamics and parameters of the system. And also, the high gain observer has such a problem that it has transient state at the beginning of the observation. In this paper, the neuro observer is proposed to improve these problems. The proposed observer complement a problem that occur from increase of gain of High-gain observer in proportion to the square number of observable state variables. And also, the proposed observer can tune the gain obtained by differentiating observational error at transient state automatically by using the backpropagation training method to stabilize the observational speed. To prove a performance of the proposed observer, it is simulated that the comparison between the state estimate performance of the proposed observer and that of sliding, high gain observer is made by using a sinusoidal input to the observer which consists of four layers in stable 2nd order system. -
In this paper we design
$H_{\infty}$ infinity controller for Induction motor with low speed operation.$H_{\infty}$ controller is applied in order to design a state feedback static controller for field oriented control of an induction motor.$H_{\infty}$ controller are linear plant can be set up using the same assumptions that are at the basis of field oriented control. Thus,$H_{\infty}$ control theory can be successfully used to set up a state feedback controller for field oriented control of an induction motor. The performances of the$H_{\infty}$ controller is numerically analysed and experimentally verified to prove the validity of the design procedure. In this paper show that performances with high robustness to variations of system parameter. -
This paper proposes the algorithm of servo- writing based on feedback error learning neural networks. The controller consists of feedback controller using PID and feedforward controller using gaussian radial basis function network. Because the RBFNs are trained by on-line rule, the controller has adaptation capability. The performance of the proposed controller is compared to that of conventional PID controller. Proposed algorithm shows better performance than PID controller.
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This paper focuses on the problem of asymptotic stabilization for uncertain time-delay systems with saturating actuator. We propose a state feedback controller which maximizes the delay bound for guaranteeing stability of the system. Then, based on the Lyapunov method, a delay-dependent stabilization criterion is devised by taking the relationship between the terms in the Leibniz-Newton formula into account. The criterion is represented in terms of LMIs, which can be solved by various efficient convex optimization algorithm. Numerical examples are given to illustrate our main method.
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In this paper, we propose a robust control technique against parameter uncertainties as well as external disturbances. It is robust control scheme using discrete-time state space disturbance observer. It does not require disturbance modeling, plant inverse modeling and/or Q filter. In frequency domain, its performance is evaluated in terms of sensitivity and complementary sensitivity as well as gain and phase margin. Finally we discuss design criterion of state space disturbance observer considering its performance in frequency domain.
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This paper studies a multirate sampled-data control for LTI systems by using the digital redesign (DR) method. In this note, to well tackle the problem associated with both the state matching and the stabilization, our nobel strategy is to minimize the linear quadratic cost function. The main features of the proposed method are that i) the delta-operator-based descretization method is applied to improve the state-matching performance in the fast sampling limit and/or the large input multiplicity; ii) the proposed multirate control scheme can improve the state-matching performance in the long sampling limit; iii) some sufficient conditions that guarantee the stability of the closed-loop discrete-time system and provide a guarantee cost for the cost function can be formulated in the LMIs format; and iv) an optimal sampled-data controller in the sense of minimizing the upper bound of the cost function is also given by means of an LMI optimization procedure.
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In the past time, the protection relay did only a protection function. Currently, its upgraded device i.e. IED(Intelligent Electric Device) has been designed to protect, control, and monitor the whole power system automatically. Also the device is desired to successfully measure important elements of the power system. This paper considers design method of a digital protection IED with a function of measuring various elements and a communication function. The protection IED is composed of the specific function modules that are signal process module, communication module, input/output module and main control module. A signal process module use a DSP processor for analysis of input signal. Main control module use a embedded processor, Xscale, that has an ARM Core. The communication protocol uses IEC61850 protocol that becomes standard in the future. The protection IED is able to process mass information with high-performance processor. As each function module is designed individually, the reliability of the device can be enhanced.
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Owing to the environmental problems as well as increasing energy prices and power plant construction costs, many researches have been made for the safe operation of distributed generations. In order to be more popularly used in parallel with the distribution network, the distributed generation and its correlation with the power system should be exactly monitored at any time. This paper presents a monitoring system which displays the important states of the distributed generation in operation and stores various measurements of the system. The proposed system constructs a data-base for developing algorithms against any faults of the interconnected system, and monitors efficiently at any place with the communication network function.
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Currently mobile devices change rapidly our life and they have considerable influences over many parts of our society. If the mobile device is applied to a control system, the usability of the control system is increased with its convenient accessibility and mobility. This paper realizes a motor control system by using a mobile device. The device uses Intel Xscale PXA-250 in which Widows CE is ported. The device is very popular at the applications of mobile devices. Also we consider its application to a mobile robot such as home service robot.
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본 논문은 철도청 사령실 통합 신호설비 구축사업에 적용할 열차 경합의 해소기법 중 열차지연시간의 수치화 기법에 대한 방안을 제시하고자 한다. 열차경합의 검지 및 해소는 열차운행의 정시성을 유지하기 위하여 매우 중요한 기능이지만 현재까지 자동화되지 못하고 지역본부별로 하나의 이벤트에 대하여 해당열차만을 고려하는 수작업의 형태로 경합해소를 수행해오고 있다. 따라서 이러한 문제를 해결하고 철도 시스템을 전역적으로 고려할 수 있는 기법이 요구된다. 이러한 시스템에서 열차의 지연에 따른 우선순위를 수치적으로 표현할 수 있는 방안이 요구된다. 본 논문에서는 열차 지연을 수치화하여 경합에 대한 최적의 대안을 제시하는 기법을 제안한다.
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An iterative robust control design for PZT using Gaussian wavelet networks is proposed. A Gaussian wavelet network with accurate approximation capability is employed to approximate the nonlinear hysteresis dynamics of PZT systems by using an iterative control algorithm. Depending on the finite number of wavelet basis functions which results in unavoidable approximation errors, a robust control law is provided to guarantee the stability of the closed-loop nano positioning system. Finally, the effectiveness of the robust control approach is illustrated through comparative simulations on a PZT.
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Kim, Sang-Hoon;Yoon, Kwang-Ho;Ko, Bong-Woon;Kim, Won-Tae;Kim, Gi-Nam;Nam, Moon-Hyon;Kim, Lark-Kyo 726
In this paper, the gain of the observer is properly set up using the fuzzy control and Fuzzy-Sliding observer(FSQ) that have a superior transient characteristic and is easy to implement compared to the existing method is designed. It estimate the differentiation of the armature current directly using the armature current measured in the AC motor. It estimate the speed of the rotor using the differentiation. It is proposed speed sensorless control method using the estimated speed. Optimal gain of speed observer(Luenberger observer) was set up using the fuzzy control and adapted speed control of AC servo motor. To verify the performance of designed Fuzzy-Sliding observer, simulation compared with fixed speed observer gain of G.B Wang and S.S Peng's sliding observer is performed. Also, it was proved the excellence and feasibility of the proposed observer from the comparison test with a speed sensor and without a speed sensor which used a highly efficient drive and 400W AC servo motor starting system. -
This paper deals with the design of a low order
$H_{\infty}$ controller by using an iterative linear matrix inequality (LMI) method. The low order$H_{\infty}$ controller is represented in terms of LMIs with a rank condition. To solve the non-convex rank-constrained LMI problem, a linear penalty function is incorporated into the objective function so that minimizing the penalized objective function subject to LMIs amounts to a convex optimization problem. With an increasing sequence of the penalty parameter, the solution of the penalized optimization problem moves towards the feasible region of the original non-convex problem. The proposed algorithm is, therefore, convergent. Numerical experiments show the effectiveness of the proposed algorithm. -
In this paper, it is suggested and implemented that a new structure of illumination control system using the adaptation control method is to control a number of illuminators. IDs is given to each illuminator controller, the systems are connected in serial, and then the main system controls the on and off of the power supply, intensity of illumination, and a failure check.
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This paper proposes a method of fault diagnostics on switching mode power supply. When the error of switching mode power supply cannot be found when the conventional diagnostics is performed, this proposed method first performs diagnosis on the switching mode power supply strictly to judge the operating condition. This method analyzes the PWM wave which depends on the load change, to make sure the feedback control of the power supply to diagnosis the operation of the power supply system.
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The disturbance observer is effective in enhancing the performance of position control in high speed optical disk drive systems(ODDS). It is known that error based modified disturbance observer (EM-DOB) is more effective structure than general DOB. It has a simple structure and realization, but it loses robustness. We propose a dual modified disturbance observer(Dual mDOB). It consists of internal loop EM-DOB and external loop DOB. Those loops are designed for different objects. We see that the dual mDOB is an effective method for tracking performance.
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In this paper, we describe a Control Element Drive Mechanism(CEDM) operation test using a Power Controller. By testing, we can catch the mechanical and electrical characteristics of CEDM and obtain the information about the improvement of CEDM and the design of CEDM power cabinet. The power controller for CEDM introduced in this paper can input firing angles directly into gate drive circuits of thyristors so that this method can be used to derive the maximum and minimum values of firing angles within available limits for a 3-phase half-wave rectifier. Angle inputs help us understand each coil's response characteristics. Since this power controller generates a serial sequence for CEDM insertion and withdrawal operations, we may judge whether CEDM works correctly as expected or not in each phase of a step movement.
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An electric precipitator in a thermal electric power plant is essential equipment for preventing air environment pollution. However, it is difficult for the existing control systems to make efficient effects on dust collection. This is because AVC and ERC consist of independent, separate systems in the existing systems. To solve this problem, we developed an intelligent distributed control system, which makes optimal control possible through connection operations between the control systems. In this paper, we analyzed system performance and fly ash reduction effects through the developed system structure, development contents and its actual application to power plant.
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The pantograph should supply the electrification equipments of a train with the current from the overhead catenary system over a broad range of speeds. For a high-speed electrical train, the dynamic interaction between the pantograph and the overhead catenary system causes the variation of the contact force. As the operational speed increases, the variation of the contact force increases. The contact force variation can cause contact losses, arcing and sparking. If the spark happens between the pantograph and the overhead catenary system, the EMI(electro magnetic interface) and noises may occur. After all, the quality of current collection is deteriorated. This paper deals with the dynamic characteristics analysis between pantograph and catenary system using block pulse function.
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In rotating systems, backlash imposed limitations on the quality of control. System with gear is an example where this is a well-known limitation. In order to increase the controller performance, we design a fuzzy system to compensate the backlash effect. We prove that under certain conditions the fuzzy compensator guarantees that the backlash output converges to the desired trajectory. Simulation results show that the fuzzy compensator is robust to the backlash parameter.
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The ultrasonic piezo motor is a new type motor that has an excellent performance and many useful features that electromagnetic motors do not have. But, it suffers from severe system non-linearities and parameter variations especially during speed control. Therefore, it is difficult to accomplish satisfactory control performance by using the conventional PID controller. In this paper, to achieve the precise control, we analyzed response time & change with a driving time, and proposed PD controller combined with neural network. The backpropagation algorithm is used to train a given trajectory. The effectiveness of the used method is confirmed by experiments. The effectiveness of the used method is confirmed by experiments using the ultrasonic motor made in Korea.